Perception and Reality
If you’ve been following the reports about the Mariners starting pitching candidates this spring, you’ve no doubt read about how Hisashi Iwakuma’s “struggles” have been concerning to the coaching staff, which is part of the reason why there’s a chance he begins the year in relief, rather than as the #3 or #4 starter as expected. The other reason has been the “strong spring” performance of Blake Beavan, who began March on the outside looking in but has pitched well enough to give himself a real chance at starting the year in the rotation.
At least, that’s the story. Now, here’s the reality.
Hisashi Iwakuma: 57 batters faced, 2 walks, 9 strikeouts, 1 home run
Blake Beavan: 59 batters faced, 2 walks, 8 strikeouts, 1 home run
In the three things that a pitcher has some reasonable amount of control over, they’ve performed identically. Yes, Iwakuma’s given up 19 hits and Beavan just 12, but hits allowed aren’t really something that have any predictive value during the regular season, and that goes double for spring training. Evaluating a pitcher based on how many balls are falling in during Cactus League games in March is nothing short of absurd. It’s a bad use of results based analysis during the regular season, when teams are trying to win and rolling out Major League defenders on big league fields – during spring training, it’s insane.
In reality, Beavan hasn’t “performed” any better than Iwakuma this spring. If the Mariners actually do start the season with Beavan in the rotation and Iwakuma in the bullpen, it better be because they saw something in Iwakuma’s arsenal that they didn’t like, or because he showed worse stuff over here than he was throwing in Japan. There could be legitimate reasons for bumping Iwakuma from the rotation and giving Beavan the job instead – those reasons just don’t have anything to do with the results either pitcher actually got when they took the mound.