The Yankees signed Hiroki Kuroda to a one-year, $10 million contract before the season, and it was almost universally declared a smart move. Kuroda was turning 37, but since coming over to the States in 2008 with the Los Angeles Dodgers, he had been a superb pitcher. This year though, Kuroda has not gotten off to a flying start with the Yankees. Despite the fact that his ERA+ of 115 is higher than it was throughout his Dodgers career (113), the number is manipulated by two terrific starts. A good start is mixed in among the remaining four, but half of his total outings thus far have been poor.
Terrific: 4/13 vs. LAA- 8 IP, 5 hits, 2 walks, 6 strikeouts; 4/30 vs. BAL- 7 innings, 4 hits, 1 ER, 1 walk, 3 strikeouts
Good: 4/24 at TEX- 6.2 innings, 5 hits, 2 ER, 2 walks, 5 strikeoiuts
Poor: 4/7 at TBR- 5.2 innings, 8 hits, 6 runs (4 ER), 4 walks, 2 strikeouts; 4/18 vs. MIN- 4.1 innings. 10 hits, 6 ER, 4 strikeouts; 5/5 at KCR- 4.1 innings, 6 hits, 3 runs (2 ER), 3 walks, 2 strikeouts
It might be a little harsh to lump Kuroda's most recent performance yesterday in with those other poor outings, but while he was able to limit the damage to only a few runs, he didn't last long and the only people he seemed to be getting out were those at the very bottom of the Royals' batting order (as I noted in the recap yesterday, the middle of the order hit him hard). So what has gone wrong with Kuroda in half of his starts so far?
After each of his poor starts thus far, Kuroda has blamed it on his pitches not being as sharp as they could be.
4/7: "I really wish I could have continued what I had in Spring Training, but all my pitches were a little off and I didn't have one pitch I could rely on today, so it was really disappointing."
4/18: "In the past outings, I was able to go to other pitches and make adjustments. I tried many things today, but wasn't able to make those adjustments."
5/5: "Everything I had to adjust. I didn't have all my pitches, and I didn't have my command either. So basically I had to make all the adjustments I could."
Kuroda hasn't been quite as good as he was the past couple years in several rate statistics, which might explain what's been going on with the Japanese right-hander.
2010: 7.29 K/9, 2.20 BB/9, 19.6% K%, 5.9% BB%
2011: 7.17 K/9, 2.18 BB/9, 19.2% K%, 5.9% BB%
2012: 5.50 K/9, 3.00 BB/9, 14.4% K%, 7.8% BB%
Simply put, Kuroda's not striking out nearly as many batters as he had in previous years, and his walk rate is up. Those strikeouts he's not getting are turning into walks and hits, a change that will not bode well for Kuroda if he doesn't fix it going forward. Although his sinker and splitter have been fine, one of the problems Kuroda has been experiencing thus far is a slight decrease in fastball velocity, which has led to a Pitch F/X weighted fastball pitch value of -1.5 in the early goings. Pitch F/X says that Kuroda maintained an average fastball velocity of at least 92.1 mph in each of his four seasons with the Dodgers. In 2012, his average fastball velocity has dipped to 90.6 mph.
A byproduct of this decrease in velocity has been Kuroda subsequently turning to his fastball less often. Whereas last year, he threw the fastball on 22.8% of pitches, he has thrown the fastball on only 12.6% of pitches in 2012. The pitch he's turning to instead, the slider, has been thrown on 27.2% of his total pitches, but the slider hasn't had as much movement as it's typically had in the past. Pitch F/X had the horizontal movement on his slider at 1.4, 1.4, 2.8, and 1.5 for the past four seasons. This year, the movement is only at 0.6, a far cry from the previous years. Perhaps unsurprisingly, Pitch F/X has thus also rated Kuroda's slider at a -1.5 weighted value so far.
The Yankees are really relying upon Kuroda to turn in a good performance this season behind ace CC Sabathia in the rotation, especially because he was not supposed to be one of the question marks in the rotation at the start of the season. Now would be an excellent time for Kuroda to step up his game. With Michael Pineda gone for the year, Phil Hughes struggling, Freddy Garcia banished from the rotation, David Phelps a rookie, and Andy Pettitte a 40-year-old mystery, the Yankees really need Kuroda (and Ivan Nova) to add some stability to the rotation behind Sabathia, and Kuroda improving his fastball and slider will go a long way toward reaching that goal.