When assembling their bullpen for the 2021 season, the Yankees probably viewed Luis Cessa as more of a low-leverage pitcher as opposed to one in the same tier as Aroldis Chapman, Chad Green, or Darren O’Day, for example. He is the quintessential good-but-not-great bullpen arm that hasn’t always been “good” in the past.
For his career, Cessa has a 4.24 ERA and a 4.75 FIP — respectable numbers, for sure, but nothing special. Midway through the 2019 season, however, he discovered that better outcomes would result from an increase in his slider usage.
In the second half of that 2019 season, Cessa used his slider 50.8 percent of the time according to FanGraphs, and had a 3.66 ERA. Last season’s Statcast data tell us that the righty used it even more — 54.4 percent — and finished with a 3.32 ERA in 21.2 frames, albeit with a low 18.3 strikeout rate.
By now, we are starting to see a trend. Do you care to guess which pitch is he throwing even more this season? Yes, the slider. He is using it a whopping 69.2 percent of the time, and it has yielded excellent results.
Before Thursday’s game against the Orioles, Cessa had pitched 11.2 innings in the 2021 campaign, with a 0.77 ERA and 2.05 FIP. It’s still extremely early in the season, and the sample size is obviously small, but those numbers are far better than any previous year of his career.
Cessa is also limiting loud contact — his 23.1-percent hard-hit rate is among the top five percent in the league, and he has allowed no barrels so far. Cessa is actually a Statcast favorite this season, as evidenced by this chart from Baseball Savant:
Again, we may be dealing with a case of small sample noise, but there seems to be something here, which leads us to the most impressive and surprising part of Luis Cessa’s 2021 profile: strikeouts and bat-missing ability.
Cessa’s 31.9 percent strikeout rate so far would be, rather easily, a career-best. His previous high was in 2019, when he struck out 21.9 percent of the batters he faced. That number is backed by a sizable increase in swinging strike rate (SwStr%). Last season, he had a 12.5 SwStr%, and his career-high is 12.7 percent, achieved in 2019. This season? 15.6 percent.
Basically, Cessa is getting more whiffs and earning slightly more called strikes, taking his CSW (called strikes plus whiffs) to a career-best 33.5 percent, comfortably above the league average, which typically sits around 30 percent. He was at 28.4 percent in his six-year MLB tenure.
The slider has been his bread and butter, earning him a 41.4-percent whiff rate and a .210 expected weighted on-base average, or xwOBA. It’s logical that the increased usage of his best pitch led to better results, but it is somewhat surprising that’s still the case even with the extremely heavy reliance on the slider. Seventy percent is a lot, but it’s working for him.
Equally important for Cessa’s early-season success is the effectiveness of his changeup. He has only thrown it 10.7 percent of the time, but it has a 40-percent whiff rate and a .125 xwOBA. Last year, it had a 25.8-percent whiff rate, so it remains to be seen if it’s something that will be corrected with a larger sample or if he truly improved the effectiveness of the pitch.
Cessa’s walk rate has been somewhat elevated to start the year, at 12.8 percent, but if this is the trade-off for who he is now, then the Yankees will surely take it. He has a long way to prove this is not a fluke, though.