Hiroki Kuroda did not look good yesterday. His command was off, hitters were squaring him up, and he seemed to tire very quickly around the 80-90 pitch mark in the 5th inning, an inning he was unable to complete. Paired with a similar failure to close an inning in the 7th on Tuesday night against the Tigers, the talk of Hirok slowing down in August as he did last year is quickly picking up. Is it warranted? 2 starts is hardly enough to say definitively, but there are some SSS numbers worth considering for either side of the argument.
The Contact Rates- The split in Hirok’s 2 August starts is 30.6% LD/38.9% GB/30.6% FB. That’s by far the worst monthly split he’s had all year. It’s the first time his LD % against has been over 22.0% and the first time his GB rate has dipped below 44.0%. This isn’t guys sneaking seeing-eye singles through holes in the infield. This is guys seeing what Kuroda is throwing, putting a good swing on it, and smacking the ball squarely all over the ballpark.
The Walks- None in his 8/5 start against Detroit, but 4 yesterday,. That included the final 2 batters Kuroda faced, both with 2 outs and the last with the bases loaded to bring in a run. His inability to locate his sinker yesterday was not isolated to just that start. In these 2 August starts, Hirok has thrown his sinker for strikes less often (64.6% compared to 70 in June and July), gotten fewer swings on the pitch (40.5% compared to low-50s in June and July), and gotten fewer whiffs on it (3.8% compared to mid-6s) than he did in the last 2 months. The sinker is Kuroda’s most important pitch. When he isn’t commanding it, that’s usually not a good sign.
The Velocity- For all the perceived problems Kuroda is having command his sinker, he hasn’t lost any juice on it in August. The 91.3 MPH average velocity over the last 2 game is a tick higher than he was throwing the pitch during his best months of June and July and he wasn’t experiencing a big drop-off late in his start yesterday. Had that happened or had the average in these last 2 starts been noticeably lower than previous months, the issue of fatigue could be brought into play. Because there’s been no drop in velocity, the issue could be something as simple and correctable as a mechanical flaw.
The Hitting Results- While there have been plenty of line drives hit off Hirok in the last 2 starts, opposing team really haven’t been knocking him around. The .244/.327/.357 slash line against him is very similar to the .248/.295/.381 from last month, which was one of his strongest months of the season. The high LD rate suggests he may be getting lucky on balls in play, but this low batting output on those line drives suggests maybe 1 or 2 of them were bad luck hits that fell into open spots. It would be one thing if he were giving up a ton of doubles and home runs. That’s not the case though, so to say he’s starting to fall apart based on a high number of singles from 2 games would be premature.
It’s worth nothing that Hirok’s last start of July saw him throw 115 pitches. That number was the highest for him this year and only the 8th time in 24 starts that he’s thrown 100 or more. Perhaps that extra workload has sapped enough from him to negatively impact his command. Perhaps he’s just been victimized by a few good swings on a few bad pitches. Whatever is really going on, the last 2 outings are not enough to say it’s definitely the start of Hirok’s late-season regression. We need to see what the next start brings and what the rest of the month brings before we really start getting concerned.