Wacha baffling hitters with his changeup

In eight starts since re-joining the rotation at the beginning of September, Cardinals rookie Michael Wacha is 5-1 with a 1.20 ERA. He’s been even better in the postseason, going 3-0 with a 0.43 ERA between the NLDS and NLCS.

One of the primary reasons for his ascension has been the effectiveness of his changeup, long considered his best offspeed pitch. Through Sept. 19, opponents were hitting .213 against it. Ever since, they’ve hit a paltry .094. He is also throwing the pitch more often. He’s thrown it in 24.8 percent of his pitches over his past four starts.