PT TOMORROW: NL West—Anyone ready to step up in ARI rotation?

Arizona Diamondbacks

The Diamondbacks began the year with essentially the same starting rotation that ended last season—i.e., one that finished with a combined 3.61 ERA, good for third best in the majors. But with Taijuan Walker (RHP, ARI) now on the shelf for the rest of the year with a torn UCL, the rotation’s depth will no doubt be tested.

Getting the first call was 27-year-old right-hander Matt Koch (RHP, ARI). Known more for his control than overpowering stuff, Koch earned a 6B rating in the Minor League Baseball Analyst while failing to crack the team’s top 15 prospects list. Koch posted an 11/2 K/BB in 14 spring innings, and went 6 innings (1 ER, 4 K, 2 BB) in his first start against the Padres, which was enough to warrant a...

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