We Are Ignoring J.A. Happ At Our Own Risk

If there was any mystery about J.A. Happ’s status with the Yankees, it got resolved on Thursday, when general manager Brian Cashman announced that the 37-year-old would begin the 2020 season as the team’s fifth starter, as reported by the YES Network. The lefty has elicited a yawn in early NFBC drafts, as his 474 ADP has him well outside the top 150 pitchers. Maybe the previous lack of clarity around his role has played some role in the low level of interest, but given the dropoff in his productivity from 2018, this news probably won’t move the needle much on Happ’s ADP. That means, at best, that Happ won’t be viewed as anything more than a reserve round pick in 15-team mixed leagues.

It was a mere two seasons ago that Happ was a top 20 starter in terms of Roto value (and a top 25 pitcher overall), sporting a 17-6 record, 3.65 ERA, 1.13 WHIP and 193 strikeouts in 177.2 innings. It was Happ’s fourth straight season with an ERA in the 3.00s. That performance is being heavily discounted as we head into the 2020 season, largely due to Happ’s ERA soaring to 4.91 in 2019. The fact that he is now in his late-30s amplifies last season’s slide. Also, while Cashman has ensured us of Happ’s place in the starting rotation for the start of the season, he would seem to be at risk of losing it once Domingo Germán has completed serving his 81-game suspension for his violation of Major League Baseball’s domestic violence policy in early June. He could also face competition from Jordan Montgomery, Jonathan Loaisiga and prospect Deivi Garcia, among others.

While Happ’s age is not in dispute, and we can all appreciate the pitching depth the Yankees have assembled, we can also take a closer look at what was behind his downfall in 2019. It is easy to correlate the decrease in his effectiveness with his age and write him off as a victim of inevitable decline, but that would sell him short. Despite his much higher ERA, there was much about Happ’s 2019 season that bore a resemblance to his 2018 season. His swinging strike rate remained virtually steady, ticking down from 10.4 to 10.3 percent, as did his walk rate, which remained in the 7.0-to-7.5 percent range for the fourth straight season. Happ continued to throw his four-seam fastball for roughly half of his pitches, and his average velocity on the pitch dropped only slightly, from 92.7 to 92.1 mph. The rest of his pitch mix was largely unchanged from 2018.

There were two notable changes, and both were negative. His strikeout rate swooned from 26.3 to 20.7 percent, even though his swinging strike rate was not discernibly worse. Happ allowed foul balls at a lower rate, and partly because he threw less frequently in the strike zone, his called strike rate was down as well. Regression in his foul ball rate to 18.8 percent was to be expected after inducing them at a 20.6 percent rate in 2018. The drop in his called strike rate, from 16.7 to 15.0 percent, is more concerning, but it’s a sharp enough decrease that we could reasonably expect some regression upward.

It’s harder to look past Happ’s home run problem. The jump in his HR/9, from 1.37 to 1.90, far outstripped the major league-wide 20.7 percent increase in HR/9. Of the 34 home runs Happ allowed, 25 came off his four-seam fastball. Throughout 2018 and most of 2019, he was typically locating his four-seamer high in the strike zone, and in 2018, that worked to his advantage. Opponents were more likely to hit for extra bases (as measured by ISO/P) when connecting with his pitches in the lower-center portion of the zone than when they hit his higher offerings. His average exit velocity allowed on flyballs and line drives (EV FB/LD) off his four-seamer was 93.2 mph — right at the median of all pitchers who allowed at least 100 batted balls in that category.

Last season, hitters appeared to have adjusted, hitting for much more power on Happ’s four-seam fastballs that were higher in the zone. Behold the change, as revealed by his 2018 and 2019 heatmaps for ISO/P on his four-seam fastball.

In 2019, Happ’s EV FB/LD on his four-seam fastball rose to 95.5 mph, giving him the third-highest mark out of the 47 pitchers who allowed at least 100 flyballs and line drives on four-seamers. That’s a huge problem for a pitcher in the American League East, and especially for one who plays home games at Yankee Stadium. It’s not an unsolvable problem, though. For example, he could try throwing more sinkers. Not only has the pitch yielded a ground ball rate over 60 percent for four seasons running, but his HR/FB and EV FB/LD on his sinker dropped from 2018 to 2019.

Alternatively, we could see what Happ did differently over the final seven weeks of the 2019 season. He had a dramatic turnaround during that stretch, compiling a 3.27 ERA and 1.14 WHIP with 45 strikeouts and five home runs allowed over 41.1  innings. Incredibly, he threw more four-seamers and fewer sinkers during this more successful period. Happ simply zigged where hitters had zagged, locating his fastball lower in the strike zone and also farther away from right handed batters. Here are the pitch percentage heatmaps for his four-seam fastball for 2018 and the portion of 2019 prior to when he improved (through his Aug. 9 start at Toronto, to be exact) as compared to the corresponding heatmap for his final seven starts of 2019.

There are still reasons to be skeptical of using Happ’s late-season surge as a basis for bumping him up your 2020 rankings. It’s a small sample. We won’t know if Happ will follow a similar location pattern this season, and if he does, whether it will be similarly effective. And as noted above, he will be another year older and will likely be facing some tough competition from other prospective starters. However, given that Happ did many of the same things he did when he was a top 20 starter just two years ago, and acknowledging that he successfully made adjustments late last season, we are doing ourselves a disservice by completely ignoring him. He is still worth a late-round gamble in 14- and 15-team leagues, and should he go undrafted, he belongs on our watch lists.

Statistical credits (in addition to FanGraphs): Baseball-Reference, Baseball Savant.