Grayson Rodriguez's Fastball Location. Jake Bloss' MLB Debut
Grayson Rodriguez, Jordan Montgomery, Jake Bloss
Orioles Grayson Rodriguez has stopped throwing his four-seam up-in as much against right-handed hitters over his last 4 starts (heatmaps below). Righties hold a .518 xSLG against him during that span, but it’s not because of his fastball. His breaking balls have both had rocky batted-ball results. His slider whiff has also dropped from 39% down to 29%. We also see more fastballs middle-up to lefties as opposed to up-away. Both fastball locations are more toward his glove side. I wonder if something in his mechanics is causing the drift to his glove side, rather than a conscious change in targets. The byproduct of this has (somehow) made his breaking balls less effective? I’ll be monitoring how this trends over time. I don’t think there’s reason for concern, but the lack of whiffs versus righties of late appears tied to this glove-side drift. 🤔
Rodriguez has also started throwing his curveball more. Comparing June vs May, the pitch’s usage has jumped from 16% to 27% versus lefties and 7% to 15% versus righties. Driveline Stuff+ of 98 on the pitch. It likes the slider more (109 Stuff+). I wonder whether this is just a natural ebb and flow of usage during the season, trying to polish a peripheral pitch for deeper season usage/success. It’s been successful, but the slider is better.
Astros Jake Bloss had a rocky debut—3.2 IP, 6 H, 2 ER, BB, 2 K on 79 pitches. He’s a 5-pitch arm with plus extension and an average release height. Fastball, slider, and sweeper with an occasional curveball to righties. Fastball and curveball with a peripheral changeup and slider to lefties. His slider is his best pitch. It’s 87 mph with 6” vertical break and 7” sweep. FanGraphs Stuff+ of 125. His baseline fastball traits look good too (FanGraphs Stuff+ of 100). The extension pulls down his release height so his slightly above-average vertical break plays up even more. I had him 1 mph harder on his fastball at Double-A this year. While we usually see a debut velo bump, we have the inverse here. I assume this will correct up to sitting 94-95, which would help a lot. 🥳
His changeup (splitter?) doesn’t look great from a specs standpoint, minimal vertical or velocity separation from his four-seam. But it gets a FanGraphs Stuff+ of 100 (unsure why). It did play well in the minors despite low usage. His archetype of pitcher is attractive because it’s based around a good fastball and slider with 3 other workable shapes. Driveline Stuff+ has the curveball at 90 as well, probably a pitch he’s throwing a bit much, but the Astros like curves (think Hunter Brown). I’d hold here and see how another start looks.
Dbacks Jordan Montgomery has strung together 3 good starts after a miserable start to his 2024. His four-seam and sinker usage to righties has risen from 47% to 55% while his curveball and changeup have dropped slightly. His swing-miss has shot up and he cut his xSLG ~150 points. Separating his bounceback from the quality of the Angels’ and White Sox’s lineups is difficult. It’s encouraging his good performance last night was against the Phillies. His changeup and sinker have been more precise away from righties (see changeup location below). He’s also spreading his four-seam around more, notably up-away from righties. 📈
He may have used April and some of May as his spring training, given how late he signed. I wrote earlier in the season that he wasn’t in the shadow of the zone as much. He’s corrected that and the results have followed. It’s hard to expect anything other than a ~4.00 ERA rest of season with meddling strikeout numbers and good control. Montgomery is nothing if not consistent.
