Aroldis Chapman has been mind-bendingly excellent this season. He's been much better, for longer - with better control and more prolific bat-missing - than he's ever been in his professional career. But there was only down to go once we heard things like: "Most Dominant Pitcher in Baseball," "Most Dominant Season Ever," and "Well, I guess I'll worship him."
A couple bad outings probably don't mean anything more than mere regression, but I wanted to see if there was anything to glean from Chapman's recent struggles. After all, he'll be pitching in some crucial spots on a contending team down the stretch. If there's anything at all to correct, the Reds will want to nip it. And nip it good.
Over his last six outings, Chapman has allowed a slash line of .304/.385/.696, including 2 HRs in 2 weeks. That's as many has he'd given up in 92.1 innings previously (since the beginning of his MLB career).
It's worth pointing out that this rough patch consists of just 5.1 IP and 26 batters, all from teams that could be considered contenders (including Detroit). Paring it down even further, it's just four outings in which he's allowed earned runs:
Jun 7 vs. PIT
Jun 10 vs. DET
Jun 13 vs. CLE
Jun 19 @ CLE
Again like Latos, there's a serious platoon split for Chapman this season (as there has been since Day One). It's hard to imagine lefties hitting much better than hilariously bad against him. He's allowed a .103/.220/.140 career line against, with just 2 extra base hits in 123 PAs and an math-error-like 57 Ks. He's better than his career line against lefties this season, having stopped walking them almost entirely.
Chapman's trevails haven't been brought on wildness of the type he encountered last season. There's been a wild pitch and a hit batter in there, but only 2 walks in 5.1 innings. Clearly, he's not putting the ball where he wants to, but he's also not erratic.
One curious thing about Chapman's recent struggles is that he's gotten touched up by some weak hitters. Here's a complete list of players who have gotten a hit off Chapman over the four outings above: Clint Barmes (2b), Michael McKenry (2B), Austin Jackson (2B), Jose Lopez (HR), Shin Soo-Choo (single) and Asdrubal Cabrera (HR). Three of these are not like the others.
With the exception of Choo, all of those men hit righthanded. If there's anything to Chapman's recent show of humanity beyond his career platoon tendencies, it's probably in what he chooses to throw to right-handers and how he throws it.
Chapman going to the fastball 88% of the time this season, but he's had little reason to change that mix. He's thrown heat to righties even more often (90%), giving a right-handed batter who isn't paralyzed with fear the option to wait for a fastball on or near the spot where he wants it. That doesn't mean Chapman will put it there - or that it will be hittable - but the margin of error is much lower when a hitter doesn't have to guess or change their line of sight much while also facing an opposite-handed pitcher.
Righties have whiffed 23% of the time on Chapman's slider this season, while it has not been hit for anything Pitch F/X considers a line drive. It's also a pitch that has yet to go for a HR over Chapman's career. Why doesn't he throw it more often to RHB? His recent results may give him reason enough.
HIs fastball also doesn't feature the movement seen from some other hard-throwers. He doesn't need any more nasty on it against lefties and probably doesn't need it when it's 100+ on the corners or cold zones to righties. But righties who can see it, time it and find it in the plane of their swing and can do something with it.
Chapman might not need to do anything other than ride out this stretch to remain one of the elite relievers in baseball. Setting up a slightly different target against righties, gripping the fastball slightly differently in certain situations or changing speeds more often could launch him back into the stratosphere.