Luis Cessa and his slider give the Yankees another bullpen weapon

Luis Cessa may not be the flashiest name in the Yankees’ bullpen. After all, he is sharing the mid and late innings with stars such as Zack Britton, Adam Ottavino, Dellin Betances, Tommy Kahnle, Aroldis Chapman, and plenty of others that may be more accomplished and/or talented. However, it is fair to recognize that Cessa has evolved and morphed into a legitimate and versatile major league reliever.

Thanks to a change in his pitch mix, Cessa is putting the best ERA of his four-year tenure in the bigs, with 3.71 in a career-high 77.2 innings pitched. Like many pitchers this season, Cessa has been giving up a lot of homers (1.51 per nine innings pitched), but he has amassed his best K%, with 8.23, and also his top GB%, with 47.8.

On a roll

Right now, the man from Veracruz, Mexico, is on a nice little run. He has allowed only one earned run in his last 13.2 innings pitched, dating back to August 22 against the Oakland Athletics.

The Yankees can count on him to throw multiple innings, which is a fantastic development for any bullpen and a manager’s dream. His versatility can spare his teammates and allow the coaching staff to better distribute workloads among those with restrictions, injuries, innings caps, and other situations.

Here are his innings pitched in his last ten games: 3.0, 0.1, 1.2, 3.2, 2.0, 2.0, 2.0, 3.0, 2.2, and 2.0. The best thing is that most of those multi-inning appearances have been very good.

From 2016 to 2018, Cessa threw more fastballs than any other pitch in his repertoire, even though it was already evident last year that the pitch wasn’t very good. Judging by FanGraphs’ pitch values, his fastball has always been negative:

2016: -2.5

2017: -6.7

2018: -4.0

2019: -4.9

Cessa’s fastball velocity is clearly above average (94.6 MPH this year), but its spin is nothing special and the overall package isn’t very attractive, either. This year, though, he has made his money with the slider.

Here is his pitch mix from 2016 to 2019, focusing on the two pitches he throws most often—the fastball and slider:

2016: 50.1% FB, 23.7% SL

2017: 42.0% FB, 30.6% SL

2018: 41.6% FB, 41.3% SL

2019: 42.6% FB, 49.3% SL

See the trend? In the past four seasons, he has been cutting on his fastball usage percentage and adding to his slider, recognizing it as the better and more dangerous weapon to get hitters out.

Here are the pitch values on his slider over the last four years in the bigs:

2016: 2.5

2017: -2.9

2018: 3.7

2019: 7.8

It should be noted that he also throws a curveball and a changeup, but has used the latter only 7.2% of the time this season and he has virtually ditched the former (0.9%).

Opposing batters are hitting .194 off Cessa’s slider, with a .186 expected batting average. They are slugging .388 against it, but his expected slugging percentage is a meager .288. The pitch has a 40.3 whiff percentage and a 33.5 K%. The new pitch mix with a greater focus on the slider has been beneficial for Cessa, as he has also upped his swinging strike percentage to a healthy 12.7% this season.

His plate discipline profile also shows that hitters have been swinging more often at his outside-the-zone offerings, with 35.6% (compared to 34.5% last season and 29.5% in 2017) and their contact% is lower in 2019, as well, with 73.4% (it was 75.4% in 2018 and 76.9% the year before).

Statcast-backed success

Ball-tracking technology Statcast mostly agrees with Cessa’s performance so far. For starters, it says that he has been a little unlucky, given that his actual wOBA (.310) is .027 points higher than his xwOBA (.283).

He is limiting hard contact (33.8 hard-hit percentage, a huge improvement from the 39.9 mark he had in 2018) while also showing excellent marks when it comes to expected batting average (.224) and expected slugging percentage (.349). Additionally, Cessa’s expected wOBA con contact (xwOBAcon) is among the best in the league at .324.

All in all, by emphasizing his best pitch, which is the slider, and limiting the usage of his mediocre fastball, Luis Cessa appears to have found the recipe for success. Again, he may not have the natural talent of some of his high-profile teammates, but he has earned a defined role in the Yankees’ bullpen and has become a better pitcher in 2019.