The Yankees should be concerned about Aroldis Chapman

On Thursday, Jake looked into some early season storylines concerning pitch velocity for some Yankee hurlers, including Aroldis Chapman. Always known for his blazing fastball, Chapman has seen a downtick in velocity to start the season, resulting in some nail-biting finishes with Chapman on the mound, like Wednesday’s win in Fenway.

Chapman isn’t alone. So much talk is made about a pitcher’s trend in velocity so far this season. Just ask Kenley Jansen. For some, the situation corrects itself as the weather becomes friendlier and the early-season kinks are ironed out. April trends are usually not ones that are expected to last over a 162-game season. However, Chapman may be in danger of becoming an exception.

Chapman may still throw very hard, but like anyone would expect, his fastball has been slowing down over the past three seasons. In his first season with the Yankees (and eventually the Cubs) in 2016, Chapman averaged 100.9 mph on his fastball, the best mark in the majors. Back with the Yanks last year, his velocity dipped slightly to 99.7. To start the 2018 season, Chapman’s fastball is down to an average of 98.4 mph, as the alarming (but not surprising) trend continues.

It’s not just the steady decline in velocity that raises eyebrows. Looking at the graph, Chapman has never come out of the gate throwing this “slowly” in the past two seasons. The early blip in the 2017 season was right before he hit the DL, and as you can see, he was throwing consistently over 100 before his injury. He came out of spring training in 2016 throwing consistently over 100 mph as well. That’s not the case so far in 2018.

The issue is what Chapman becomes without his overpowering fastball. Take away a heater thrown consistently over 100 mph, and Chapman is more of an average reliever. Just look at how many hard-throwing relievers the Yankees have at their disposal. They aren’t as rare as they used to be. Chapman’s off-speed arsenal is mainly effective due to the drastic difference in velocity, not due to bite or movement. As the gap in velocity closes, Chapman becomes more hittable. That gap has been shrinking for the past three seasons, and Chapman doesn’t have access to the Fountain of Youth.

We’ve seen Chapman try to overcompensate when his velocity isn’t there, which results in a loss of command. It showed in his appearance against the Orioles when he walked a pair of batters in one inning of work. Fortunately, he escaped a jam, but he might not be so lucky if his fastball is no longer blowing hitters away.

Thanks to splurging for Chapman on a five-year, $86 million contract prior to last season, the Yankees will likely have the lefty in their bullpen until the end of the 2021 season, when Chapman will be entering his mid-thirties. His fastball may be entering the mid-nineties by then, or worse. We’ve seen Chapman fight off brutal slumps like he did last year, but you can’t fight off the aging process, and with age comes decline. We may be watching the beginning of that decline right now.