Tanner Bibee Changed His Release. Tanner Houck's Dominance
Tanner Bibee, Tanner Houck, Graham Ashcraft
Guardians Tanner Bibee’s release point is down ~3” in his last 4 outings. And he’s put together 3+ consecutive good starts for the first time this season. 24.2 IP, 1.82 ERA, 5 BB, 25 K in that span. We’re seeing a few effects of the lowered arm slot. First, his velocity is up 1 mph. He’s sitting above 95 mph in his last 4 outings. The pitch also has the same vertical break, making the approach angle of the ball flatter upon entering the zone. Second, his curveball looks more like a sweeper and he’s backed off usage. It added 2.5” vertical break (dropping less) and 2.5” more sweep. I think this is more a byproduct of lowering his arm than a conscious change in curveball shape. 👍
To lefties, his fastball results have improved. Swing-miss doubled from his first 8 starts to his last 4 and the xSLG is down 300 points. He’s still throwing it inside to lefties more than last year—which I don’t understand—but the location has hovered more toward middle-up in these last 4 outings. To righties, he’s pounding the outer third (see heatmaps below), which feels like a byproduct of his lower arm affecting ball placement rather than a conscious location change. It’s tough to gauge what’s going on here. My bet with arm slot drops is often that something changed mechanically in a pitcher’s lower half and that causes the arm to lower at release. I’d bet it’s more conscious than a byproduct of injury based on the velo jump and left improvements. I think a “stock up” or “back on track” tag after a 4.91 ERA to start the year is appropriate.
Reds Graham Ashcraft has lost some effectiveness to righties. The big change for him this season was throwing a lot more sinker to righties. In May, his cutter swing-miss has been cut in half and his xSLG versus righties has jumped 200 points to .500. Given his shapes look largely the same, the only theory I have is that his locations have changed slightly. His slider is in the zone more, away from righties more as opposed to down-away for chase whiffs (see heatmaps below). While the cutter is in the same spot to righties, I’d theorize the deterioration of his slider performance is due to the location of this cutter. How locations interact with one another between pitch types and in sequences matters. How much? We don’t really know, but it feels like a culprit here. 🤷♂️
Red Sox Tanner Houck’s last 3 starts have been great: 20 IP, 16 baserunners, 4 BB. 18 K. Two small usage changes. First, his sinker usage to lefties has increased and he’s throwing it in the zone a lot more middle than just away (see heatmap below). He’s also using his slider more backdoor to lefties. Houck’s splitter usage to righties increased 10 percentage points, which is the more intriguing tweak given the pitch has missed bats on 70% of the swings taken over his last few outings (small sample). No notable location changes to righties. 🧦
Despite a small repertoire, Houck remains unpredictable because he throws 3 pitches >15% to either handedness of hitter. At least, that’s one of my theories. He might just also get a ton of unexpected drop on his sinker. Houck holds a 1.85 ERAz with a 2.13 FIP through 74 IP. He’s pacing to shatter his career-high IP total of 119 back in 2018. I’m interested to see how the Red Sox manage his innings. Very little suggests this won’t continue, even if he’s more of a 3 ERA pitcher going forward than a sub-2.
