How Aroldis Chapman has evolved this season

The discussion surrounding Aroldis Chapman this spring centered on his diminished velocity, and for good reason. Though everyone was accustomed to seeing him hit triple digits with regularity, Chapman was throwing his once-legendary fastball in the mid-90’s. Chapman’s velocity has resurfaced somewhat in recent weeks and he looks closer to the flame-throwing version of himself, but he’s also been less erratic than usual this season.

As dominant as Chapman has been as the Yankees’ closer, he’s always had moments where his lack of command puts you on the edge of your seat. He holds a career 4.13 BB/9 rate, and that number spiked to 5.26 BB/9 last season, according to FanGraphs. In fact, Chapman ranked in the bottom 2% of MLB with a 14.2% walk rate last season, according to Statcast. It’s entirely possible that knee tendinitis contributed to his lack of command, but he certainly looks healthy right now. Through his first 15 games of 2019, Chapman’s walk rate is down to a career-best 1.98 BB/9 and he’s pitching to a strong 2.45 ERA in 14.2 innings.

On the other end of the spectrum, the left-hander is also giving up hits at the highest rate of his career. He’s surrendering 7.6 hits per 9 innings so far this season, compared to 4.2 last season. It’s essential for Chapman to give fewer free passes, as his pure stuff starts to trend downwards on the wrong side of 30. A free pass here and there isn’t of much concern when you’re posting a league-leading 16.3 K/9 like Chapman did last season, but he’s not striking batters out at the same rate this year. His K/9 is down to a more human– albeit still very strong –12.5 K/9.

It’s hard to say if Chapman’s making a concerted effort to pound the strike zone, or if he’s just doing a better job executing his pitches, but the bottom line is that he’s going right after batters more than ever. He’s thrown a first pitch strike to 69.6% of batters so far this season, a substantial increase over his previous career high of 61.9% in 2017 and an even more noticeable increase from the 58.5% he posted in 2018. The Yankees have to be happy to see Chapman locating his pitches and throwing more first pitch strikes as he inevitably loses some of the juice on his fastball over the last three years of his five-year $86 million deal.

Nobody’s going to mistake Chapman for a crafty lefty at this stage in his career, but he now ranks 12th in MLB, according to Statcast, with an average four-seam fastball velocity of 97.4 mph. It was only two years ago that he led MLB with an average fastball velocity of 100 mph. He’s throwing more sliders than ever and pitching to contact at a higher rate than we’ve seen previously. Batters are connecting on 81.1% of swings at pitches in the strike zone, the highest of Chapman’s career, but his opponents’ average exit velocity of 85.1 mph ranks in the top 9% of the league and is actually better than his career average of 87.4 mph since Statcast started tracking in 2015.

Chapman is still throwing heat and shutting it down for the Yankees in the ninth inning, but he’s starting to do it a bit differently in his age-31 season. That he’s managed to do so portends well for his future performance as his physical skills inevitably decline further.