Jack Flaherty's Velocity. Mitch Keller Concerns?!

Mitch Keller, Jack Flaherty, Luke Weaver, Brandon Pfaadt

• Pirates Mitch Keller has had a rough past 4 starts. The most apparent thing is that his release point has fallen 2-3” when compared back to April/May. This could be a byproduct of a slight extension increase. His four-seam has lost 1” vertical break and his sinker has lost 1.5” arm-side run, both pitches are around the same velocity. They’re not as separated on a pitch plot. FanGraphs Stuff+ downgraded the four-seam from 107 to 99 and the sinker from 102 to 85. Only the sinker, however, has deteriorated from a damaging contact standpoint. Four-seam performance has actually improved from a .388 to .303 xwOBA on contact despite a small drop in whiffs (small sample). Sinker to righties appears more over the plate, four-seam more up in the zone. Four-seam slightly more up in zone to lefties as well.

  • His sweeper has lost about 2” sweep as well, velo slightly down. His cutter has 2-3” less vertical break to it and 2” more sweep at a slightly lower velocity (not behind the ball as much, makes sense with lower release height). He’s upped his sweeper usage to lefties considerably too. Both of these changes, however, aren’t affecting the grade of the pitch much per FanGraphs, yet their xwOBA on contacts have both jumped a lot. It’s hard to isolate off blame in a pitcher who throws 4-5 pitches to each handedness. Easy answer is that the mix is off. My guess is that the release point drop has affected shape/look of his fastballs, which has caused secondary issues. Head-scratcher otherwise. 🦜

• Orioles Jack Flaherty averaged 94.1 mph with his fastball yesterday, the highest of his season. It’s interesting that everything he threw >95 mph came in either the 1st or the 6th inning. Adrenaline in the 1st, emptying the tank in the 6th? His fastball release point was the lowest of his season. 1-2” lower than his July average, 2-3” lower than April/May. Orioles will make some tweaks, but the velo jump feels like adrenaline + prove-it-to-my-new-team thing, rather than Orioles devil magic. What’s being charted as a change in “cutter” usage appears like he was just ripping slider harder to me, and it got reclassified. Need more data there. 🔥

• Reds Luke Weaver added a cutter on July 23. He used it 35% of the time yesterday against the Cubs, the highest usage of his past 3 starts. The pitch has 12” vertical break with 3” glove-side movement at 90-91 mph. FanGraphs Stuff+ has it at 104. It’s generating a 38% swing-miss rate, well above average. xwOBA on contact is below .300 as well. Looks like his best pitch from a results standpoint. He’s throwing it to either handedness, generating 50%+ swing-miss in a small sample to right-handed hitters, lefties xwOBA on contact is below .200. Location is primarily up, up-in to lefties and down-in to righties. ✂️

• DBacks Brandon Pfaadt has increased his sweeper usage in his last 2 outings. The increase is most apparent in how much he throws his sweeper to left-handed hitters, generally considered a bad idea. It was used 15% of the time back in May to lefties, and it’s up to 33% in his past 2 outings. His location with it is down in the zone, feel for keeping it down was good yesterday. Right-handed sweeper usage up only 3 percentage points, key there is a 14 percentage point reduction in four-seam usage, primarily to throw more sinkers. Sinker is generating good contact quality despite no whiffs and a poor FanGraphs Stuff+ (82). 🐍