Alex Cobb Will Be One of The Gems of This Free Agent Class

NOTE: This article was originally published on FanGraphs on November 30, 2017.

Of the pitchers hitting the free-agent market this winter, Alex Cobb is not likely to receive the most fanfare.

Aces Yu Darvish and Jake Arrieta will command contracts north of $100 million. Closers Wade Davis and Greg Holland will do their best to secure four-year deals with big price tags. The whole world is watching every development in the Shohei Ohtani saga. Hell, among midmarket starting pitchers, MLB Trade Rumors predicts Lance Lynn to receive a more lucrative contract than Alex Cobb.

Cobb, who broke in as a full-time starter with Tampa Bay in 2012, has historically shown great promise and good-but-not-great results. He averaged 2.5 fWAR from 2012-2014, lost the next two seasons to Tommy John surgery, then came back with a 2.4 fWAR season in 2017. Cobb has never started 30 games in a season, nor has he ever thrown 200 innings. These facts are concerning to some, but I would argue that he is one of the wisest investments one can make this offseason.

Alex Cobb has evolved as a pitcher through pitch selection. Cobb has a great curveball. You either already know that, or you’re about to find out. He also mixes in a four-seam fastball, a splitter, and a sinker. Right now, curveballs are all the rage in baseball, resulting in tremendous success for pitchers like Rich Hill, Trevor Bauer, and Lance McCullers. They throw their curveballs so often that we can consider the breaking ball, not the fastball, to be their primary pitch. Like Hill, Bauer, and McCullers, Cobb has a quality breaking ball, so it stands to reason he should throw it more often and perhaps eschew his mediocre offerings. With Brooks Baseball, we can track the usage rate on each of his pitches throughout the season.

Look at the first couple data points for the usage rates on his pitches, and then compare them to his points at the end of the season. It’s clear that Cobb began to realize he works best by using the fastball and the curveball exclusively, so he increased his usage rate on those pitches and gradually phased out the splitter and sinker.

The question for Cobb is whether this was a good idea. In Cobb’s career, he’s only posted a strikeout-to-walk percentage (K-BB%) above 15% twice, and only ever so slightly so. He’s not bad in that regard, but it’s not where he makes his bread and butter. Fortunately for Cobb, he is one of the better pitchers in the league at inducing ground balls, which we know is favorable contact. The more grounders Cobb induces, the better he gets, and his curveball is a ground-ball machine. Consider the correlation between the rate at which Cobb increased his curveball usage and his ground-ball rate (GB%) throughout the season:

That’s a pretty strong correlation. It seems that Cobb is ready to join the Hills, Bauers, and McCullerses of the world and ride a high breaking-ball-usage rate to breakout success. Of course, it’s never going to be that easy for Cobb or anybody, but let’s go through one of his starts and parse what we can from the good and bad.

On September 4, Cobb pitched against a red-hot Minnesota Twins lineup and had one of his better starts of the season. His first batter of the game was second-half monster and fly-ball connoisseur Brian Dozier, and he managed to get him out on the first pitch.

It’s been proven that batters from the “fly-ball revolution” can be neutralized if you throw them high fastballs. These hitters are swinging up to lift the ball, but it’s difficult to put much lift on a high pitch coming in fast.

We’re going to focus on the curveball throughout this piece, but here is a fun fact about his fastball. Cobb’s heater sits at 92 MPH and had a spin rate of 2101 RPM this season, which seems pretty pedestrian. However, among starting pitchers with at least 100 batted-ball events involving fastballs, Alex Cobb’s has the 31st lowest exit velocity (87.1 MPH). To put this in perspective, that’s a better mark than James Paxton, Chris Sale, Max Scherzer, Jon Gray, Justin Verlander, and Luis Severino.

Cobb was smart to bait Dozier here, and he reaped the benefits with a first-pitch out to begin the ballgame.

In the second inning, we see Cobb pitching out of the stretch and unleashing a curveball that Ehire Adrianza buries into the ground. This will be the common theme today.

I mentioned earlier that Cobb doesn’t have the K-BB% of Chris Sale or Corey Kluber, so every once in awhile he walks batters. The common thought is that Cobb, who throws so many breaking balls, might end up behind in the count thanks to misplaced curves. Then, to get back in the count, he throws his 93 MPH fastball in the zone, which gets crushed by every hitter expecting it.

This would be a bad habit for Cobb to fall into, but he certainly didn’t in 2017. Consider the list of pitchers who threw the most curveballs while behind in the count this season (via Baseball Savant):There’s Cobb, in fifth place, not far behind Rich Hill himself. All five of these guys have great curveballs, so it makes sense for them to Trust the Process and continue dropping the hammer rather than submitting to doom and throwing a predictable fastball in the zone.

After walking the leadoff batter to start the third inning, Cobb knew Joe Mauer could make him pay. So rather than giving Mauer the fastball he wanted, Cobb began the at-bat by dropping a curveball for a strike that even froze the great Mauer.

This changed the whole at-bat, because now Mauer didn’t know whether Cobb would be coming at him with the curve or the fastball. Cobb took advantage of his opportunity, used the fastball to get him in an ideal 1-2 count, and then he went back the curveball and got Mauer to ground into a double play.

Cobb is comfortable throwing the curveball both behind in the count and with runners on base, so he can reap the rewards and induce quite a few double plays. That is an asset. Additionally, Cobb is comfortable throwing his curve from both the stretch (as we saw against Adrianza and Mauer) and from his big windup, as you can see here.

Eddie Rosario is a good hitter who made great strides late in the season, but even he found himself to be another ground-ball victim of Cobb’s curveball.

By the fifth inning, Cobb was almost through his second time against the Twins’ batting order. At this point, they weren’t sure whether to expect the curveball or the fastball, so Cobb was often ahead in the count. Here, he has Eduardo Escobar in a 1-2 count and throws a high fastball that Escobar swings right through.

Everyone in the park was expecting Cobb to throw the curveball to finish Escobar off. From a look at Escobar’s swing, it’s safe to say he was expecting a curveball himself. Cobb’s fastball isn’t necessarily anything special, but the way he uses it to pitch off the curveball can be.

With two outs in the inning, Cobb faced his 18th batter (which would complete his second time through against the opposing batting order). He quickly got Ehire Adrianza into an 0-2 count and then unleashed his best curveball of the night, which Adrianza pounded into the ground for another easy out.

At this point, Cobb had gone through the opposing order twice, pitched five innings, and only given up one run. Teams around the league are beginning to realize that most of their starters simply shouldn’t go out for the third time through the order, even if they are rolling. The Houston Astros just rode using Lance McCullers, Brad Peacock, and Charlie Morton in tandems all the way to the World Series. Those three guys are valuable pieces, and if Cobb is utilized liked this, so is he.

Unfortunately for Cobb, his pitch count was at 85, so his manager decided to bring him out for another inning. The Twins got their third look at Cobb, and I don’t need to cite the statistics to you about what happens at this point. Hitters are smart, so they can pick up on the tendencies of a pitcher if they see him so many times. Alex Cobb, as great at he was through five innings and two times through the order, is no exception to this rule.

Here is Joe Mauer taking an 0-2 curveball from Cobb and driving it into the gap in center for a double.

The important question here is, “was that Cobb’s fault or just a good piece of hitting from Joe Mauer?” Of course, the answer in baseball is always going to be both, but you can see in the embedded GIF that Cobb doesn’t necessarily leave the pitch up. In fact, if you compare it to the curveball that Cobb threw earlier in the game to get Mauer to ground into a double play, it doesn’t look much different — maybe an inch or two higher, at worst. The bigger change is Mauer, who swings like a guy fighting to stay alive in the first GIF, then like he knew exactly what was coming and how to handle it in the second.

This is the “third time through the order” effect in a microcosm. Pitches that fool batters earlier in the game become cookies, so the key is to relieve your pitcher while his pitches still fool the batters. Cobb should not be penalized by us for giving up a double to Mauer there; in 2018, analytical teams will be bringing in a new pitcher in these situations.

In this sense, Cobb is the first free-agent test case for the newest pitching trend in the industry — the tandem starter — one who pitches twice through the order, hopefully gets 15-18 outs, and then gives way to someone else. The Mets, who hired progressive Indians pitching coach Mickey Callaway to be their new manager, have made it clear that all starters not named deGrom or Syndergaard will be shielded from facing lineups more than twice in a game. Baseball has never experienced a shortage of five-inning pitchers in its history, but these changes in pitcher usage are leading to new premiums for these specialists.

It’s as simple as this: every team wants to stock their pitching staff with Alex Cobbs. To be clear, every team wants a Justin Verlander, but there is only one Justin Verlander; even horses Chris Sale and Corey Kluber showed significant wear and tear in October. To combat this dilemma, the Houston Astros deployed Lance McCullers, Brad Peacock, and Charlie Morton in five-inning tandems and rode them all the way to the last out of Game 7.

I expect Alex Cobb will fit into this role quite nicely for whichever team he signs with.


Aaron Judge Has Been Great in October. Umpires Have Failed Him.

NOTE: This article was originally published on The Unbalanced (Vocal Media) on October 21, 2017.

After a record-setting rookie season that may earn him the American League Most Valuable Player award, Yankees right fielder Aaron Judge has put himself in the record books in the postseason. The record he broke? Most strikeouts in a postseason series. Judge managed to do that in the five game ALDS against the Indians, striking out 16 times in only 20 at-bats. It’s incredible that he struck out 80% of the time in that series, and he’s continued that trend into the ALCS as well. Through five games, Astros pitchers have struck out Judge eight times in 16 at-bats, which is good for a 50% strikeout rate. Overall, he’s running a 60% strikeout rate in the playoffs, and yet he somehow has put up a .847 On Base+Slugging% (OPS).

Judge has been remarkable for his failures, and even more so for his successes in spite of his failures. For that reason, I decided to figure out how Judge clearly looks “on” at the plate (at the very least, far removed from his mid-summer slump) while carrying a strikeout rate that makes Chris Carter feel useful.

To be fair, sometimes we conceive notions in our head based off of what we see with our eyes. It’s well documented that Judge has the largest strike zone in Major League history, and it’s been noted that his unique measurements have tested umpires like no other. When a pitch is thrown a few inches below Judge’s knees, it has to be called a ball by umpires, but the challenge is that they are conditioned to see it as a strike, because that pitch location is in the strike zone for anybody who isn’t 6’7.” Anybody who watches a handful of Judge at-bats can see that he occasionally gets burned and ends up in a 2-2 count that should be a 3-1 count. To his credit, those setbacks don’t seem to change his approach at all; he refuses to consistently chase. Like I said, that is simply a notion conceived by my eyes — let’s see if the numbers actually back any of this up.

The first thing to consider is whether Judge himself has had discipline issues in the playoffs. Baseball Savant, our statistical tool for today, has a detailed strike zone which can divided into 25 different zones, which I’ll display for you here:

via Baseball Savant

Yes, the zone numbers go up to 29, instead of 25. That’s because 10, 15, 20, and 25 are all skipped by Baseball Savant.

You can see the strike zone represented by the green outline. Clearly, pitches in the first nine zones are absolutely strikes, while pitches in zones 11-19 are borderline, and pitches in zones 21-29 are absolutely balls. As a principle, it’s never really a great idea for a hitter to swing at pitches in zones 21-29, because they are bad pitches; difficult to hit with any authority, but certain to be called balls. Let’s look at Judge’s plate discipline on these pitches in the regular season and playoffs, with the league averages also there for reference:

via Baseball Savant

In the regular season, Judge swung at roughly 15% of the bad pitches he saw, which was an impressive 4% better than the rest of the league. It becomes even more impressive when one considers that he saw bad pitches 6% more often than the rest of the league.

In the playoffs, you see both Aaron Judge and the rest of the league increasing their swing rate on bad pitches by a percentage point or two, which can be easily explained. The league as a whole is swinging at bad pitches slightly more often, because the pitchers in the playoffs are generally of higher quality and, because batters have seen a proportionate increase in the volume of bad pitches thrown to them. However, this is not the case for Judge. While Judge has increased his swing rate on bad pitches in the postseason by a percentage point (which is still about 5% better than the rest of the league), he hasn’t just seen a slight increase in the volume of bad pitches thrown at him — it’s been a massive increase.

You’ve probably noticed that I went out of my way to make the Bad Pitch% to Judge stand out, which is no accident. While Judge has always seen more bad pitches than everyone else (nobody wants to be nonchalant with baseball’s best hitter), the rate of bad pitches thrown to him spiked in the playoffs by 3.7%. For reference, the increase that the league saw as a whole was only .8%, so Judge has had the difficulty quadrupled compared to everybody else. That he has maintained an extremely low swing rate on these bad pitches is a testament to the polished hitter he has become.

Fun Fact: One of those bad pitches from the playoff sample was thrown by Dallas Keuchel in Game 1 of the ALCS. The bad pitch, which would have been ball four, preceded a strikeout for Judge. Had the pitch been called correctly, the Yankees would have had runners on first and second (Brett Gardner) with two outs, which Tom Tango calculates to be worth .343 expected runs. Instead, Judge’s strikeout ended the inning, which I calculate to be worth 0 expected runs. The Yankees lost that game, 2-1.

Now that we have established that Judge deserves our praise, let’s examine whether that same goodwill has been granted to him by umpires on close pitches. To refresh your memory, here’s how Baseball Savant breaks down their strike zone:

via Baseball Savant

Because the strike zone is represented by the green outline, we can’t definitively say that pitches thrown in zones 11-19 are strikes or balls the same way we can for pitches thrown in zones 1-9 and 21-29. Thankfully, our sample sizes are large enough to get some sense of what balls and strikes are, so let’s dive into the numbers on zones 11-19:

via Baseball Savant

First, let’s establish that the rate at which pitchers have thrown “close pitches” has been absolutely consistent to both Aaron Judge and the rest of the league in both the regular season and the playoffs (you can see that in the column on the right). Ironically, the only small difference is in how few were thrown to Judge in the regular season, which is incredible, considering that he was a 173 wRC+ hitter with literally the biggest strike zone ever.

From here, we can infer something interesting. If Aaron Judge saw close pitches as often as the rest of the league this season, then the rate at which those pitches were called strikes should be roughly the same as the rest of the league. That’s not exactly what happened, with Judge getting called strikes on him 4% more than the league average during the regular season. However, this is expected, considering the new challenge he was to umpires.

When we move on to the playoff statistics, we see umpires calling slightly more strikes on the league as a whole. While some might call this definitive proof of “big game bias,” the increase is minimal at most and likely the result of the playoffs being a smaller sample size. However, it’s been an absolute nightmare for Aaron Judge.

You’ll see I again made sure that one statistic stood out more than the rest. This time, I highlighted the called strike rate on close pitches to Judge in the playoffs. We know the league has experienced a minimal increase, but Judge, who was already suffering 4% more than the rest of the league, has seen his called strike rate jump from 25.8% in the regular season to 32.7% in the playoffs. This is an astounding 7% increase and unless every pitcher he’s faced has turned into Greg Maddux, I think the umpires have been seriously burning him here. Let’s dissect one specific instance from Game 5 of the ALDS:

After that brutal called strike three, Brett Gardner was thrown out attempting to steal second base to complete the double play and end the inning for the Yankees. Had the umpire made the right call, Judge would have walked, and Gardner would have been automatically moved to second base. According to Tom Tango’s calculations again, the number of expected runs with runners on first and second with one out are .908. According to my calculations, the number of expected runs with no runners on base and three outs are 0. These calls add up and they hurt.

While Aaron Judge’s 6’7” frame is certainly a challenge to umpires, it should probably be more of a challenge in April than in October. This postseason, there have been more than a handful of at-bats in which Judge has made an out (often a strikeout) after having a rough strike being called against him. Is the human error from umpires part of the game? Yes, so long as we have human umpires, but the volume of errors hasn’t been burdened proportionally between Aaron Judge and the rest of the league. A bad call turning a would-be 3-1 count into a 2-2 count can derail an at-bat, and a bad call turning a walk into a strikeout is even worse. These are things that possibly contributed to the Yankees severely under-performing their BaseRuns and Pythagorean record projections in the regular season (by an astounding 10 wins), and they can especially play a role in the remainder of the playoffs.

Let’s hope they don’t.

Taijuan Walker Is Starting to Get It

NOTE: This article was originally published on The Unbalanced (Medium) on August 14, 2017.

It’s the middle of August, and the Arizona Diamondbacks find themselves in the thick of the National League Wild Card chase. As it stands today, the D-Backs are in control of the second Wild Card position behind the Colorado Rockies. Arizona’s success has come on the strength of their starting pitching, which has accumulated the third most Wins Above Replacement in Major League Baseball, according to FanGraphs. One of their best starters this year has been longtime object-of-attention Taijuan Walker, who is our topic of discussion today.

Walker, who was acquired last offseason in an interesting trade involving Jean Segura and Mitch Haniger, has been considered a potential ace since his days as the eleventh ranked prospect in Baseball America’s 2014 edition of their Top 100 list. Now, after plenty of injuries, home runs allowed, and a trade, it seems that Walker is beginning to unlock some of the potential that earned him that pedigree back in 2014. While injuries are a big piece of the Taijuan Walker puzzle, his baseball card shows that he gave up a lot of home runs when healthy. Here is an interesting graph to consider:

It’s no surprise that there is a strong correlation between fly-balls allowed and home runs allowed, but what makes Walker’s season so compelling is that he has corrected his home run problem on the basis of decreasing the number of fly-balls he’s allowed. Many analysts looking for the kryptonite in the Fly-Ball Revolution have identified rising fastballs as a fly-ball (and subsequently, home run) suppressor. To that degree, let’s look at how Walker located his fastball in 2015, his most healthy season to date:

via Baseball Savant

The fastball was mostly concentrated in the middle of the strike zone, and it led to instances such as this:

Naturally, opposing batters like Josh Donaldson were all over those mistakes in the middle of the zone. Walker was torched to the tune of 1.33 HR/9 (and 1.81 last year). Of course, we also know that putting lift on pitches that spin as much as fastballs do is more difficult when the pitches are located up in the zone. To Walker’s credit, this is where he is concentrating that fastball this season:

via Baseball Savant

It’s done wonders for Walker, and his fly-ball rate has dropped dramatically, as you’ll remember in our first graph. Here’s masher Anthony Rizzo popping up a high fastball from Walker this year:

Of course, if Walker is cutting down on the number of harmful fly-balls he allows, the overall distribution of his batted ball profile (between pop-ups, line-drives, ground-balls, and fly-balls) is going to change. Thankfully for Walker, it seems that he is inducing enviable contact:

As long as Walker can keep that fly-ball rate low (preferably below the 35% mark) and his grounder rate high (preferably above the 45% mark), he’s going to be in business. We know that Walker throws a decent splitter, so he will always get a fair share of ground-balls from that, but he has made a change in his arsenal this year to increase his grounder rate while maintaining his strikeout rate.

Walker’s strikeout pitch has always been the fastball we’ve already discussed, so having a low 90s cutter has always seemed a little redundant. Walker decided to scrap the cutter, which he located here…

Baseball Savant

…for a low-to-mid 80s slider, which he’s throwing here:

Baseball Savant

That slider is a more compelling pitch, and as of today it’s producing a 52.9% ground-ball rate and 23.5% fly-ball rate. That’s exactly what Walker wants and needs! Let’s see it in action:

Taijuan Walker probably isn’t a number one starting pitcher, but the expectations placed upon him as a prospect were probably unfair to begin with. He’s on pace for the best season of his career, and there is potential for Walker to settle in as the third starter in a competitive rotation. Arizona paid a high price to acquire Taijuan Walker, but thankfully for them, he will not be a bust as long as he stays healthy.

What Xander Bogaerts’ Different Approaches Tell Us

NOTE: This article was originally published on The Unbalanced (Medium) on June 25, 2017.

A lot of internet ink has been spilled on the Fly Ball Revolution in baseball. Some of it has certainly been done by me, and with the outburst of home runs leading up to this season, it is firmly one of the main themes of the 2017 season. Of course, the idea that a batter should do more to hit the ball in the air, and subsequently more power, isn’t a novel idea; it’s just being brought to the forefront by analysts. At the same time, it’s important to establish that increasing launch angle does not necessarily predicate more offensive success, as concluded in a study by FiveThirtyEight.

This article was inspired by my curiosity in a quote that Red Sox shortstop Xander Bogaerts made in April. I recently used it in an article about Eric Thames in an attempt to demonstrate the perspective players have when making adjustments at the plate. Here it is to refresh your memory:

“I mean in April it’s not easy to hit home runs,” Bogaerts said. “You’re playing in Boston. I know the wall is right there but it’s pretty hard to hit in the cold in general. We’ll hit some home runs, especially when it starts warming up. Looking forward to a lot of home runs from a lot of guys.”

He continues:

“I mean the cold is good and bad for me,” he said. “The good part is that it helps me do a little bit less. My effort level goes down because it’s kind of cold. But when it warms up I start swinging a bit bigger. You feel stronger because of the sun and whatever. The cold is good because I just try to do more contact, don’t want to get jammed or off the end for my hands to feel pretty bad.”

I found Bogaerts’ candid comments to be interesting and wanted to verify if he really is a different hitter in April than he is in a warmer month, like June. Bogaerts has enough batted ball data this month to match his April data, so now is as good a time as ever to begin examining the effects weather might have on his hands, any changes he has made to his approach, and what those results have led to. First, let’s examine the effects of cold weather and warm weather:

via Baseball Savant

As you can see, there are improvements in exit velocity from Bogaerts on both fly-balls and line-drives. Note that while the increase is over 7 MPH on line-drives, the increase on fly-balls — about 3.5 MPH — was much more marginal. At the very least, it seems to hold up Bogaerts’ theory that he would feel stronger due to the sun. Now, with these changes in mind, let’s analyze the changes Bogaerts has made on his launch angle by comparing April and June. First April:

via Baseball Savant

He swung at some batted balls at a launch angle of around 10 or so degrees, which is just fine, except he hit the majority of them around 0 degrees or less. That led to a lot of ground-balls, which we will discuss later. Here’s Bogaerts’ launch angle in June:

via Baseball Savant

That distribution is much more consistent, and this time it is concentrated in the 10–15 degree range that he hinted at in April. Statcast measured his April and June launch angles at 4.2° and 13.2° respectively. Things are sounding good for Bogaerts so far! He is swinging a lot bigger, just as he said he would in April. But what does this mean for his results? It’s easy for us to use the new data from Statcast and automatically assume that players with higher exit velocities and increased launch angles are going to be more successful power hitters. Let’s take a look at how Bogaerts has distributed his batted balls; from what we know so far, we should see a decrease in ground-balls and an increase in fly-balls:

via FanGraphs

Sure enough, his ground-ball rate has dropped big time. That’s good, but his fly-ball rate has not increased big time. You’ll note that I labelled the statistic “True FB%” rather than “FB%.” This is because pop-ups and other infield fly-balls are included in the original “FB%.” This dilutes the concept that more fly-balls lead to more power, so I removed them from the calculation and counted them separately here. Bogaerts has avoided hitting ground-balls, but in his attempts to hit more fly-balls, he has ended up hitting a lot of weak pop-ups.

It’s incredible that the Bogaerts of April and the Bogaerts of June look like two completely different hitters, but which do you feel is the better hitter? If we use Weighted Runs Created Plus (wRC+), a statistic that encapsulates offensive value, it is the Bogaerts of June, but not by as much as one would assume. He recorded a 96 wRC+ in April, but with all of his adjustments, that number has only gone up to 109. A 109 wRC+ is nothing to sneeze at for a shortstop, but it’s also equal to the number he posted in 2015, a year in which he hit only seven home runs.

Hitting less grounders is good, but that doesn’t necessarily mean hitting more fly-balls is also good. In fact, based on the exit velocity increases in our first graphic, it’s probably in Bogaerts’ best interest to hit more line-drives. Bogaerts knows this, and he has often been a line-drive hitter; that’s why he has recorded a .342 BABIP in his career. None of this is to determine whether Bogaerts is a valuable hitter or not, because he undoubtedly is. However, we have been able to learn from Bogaerts that there are still many ways to be a valuable hitter, and that it’s most advantageous for hitters to simply play to their strengths — whatever they are.