In the sixth-inning, Wacha couldn't dodge a Matt Adams foul ball that was drilled into the Cardinals dugout, ricocheted off the wall and hit the right-hander in his pitching arm.
Wacha wouldn't come back out for the seventh, despite having thrown six shutout innings and only 88 pitches. The Cardinals announced that Wacha suffered a bruised right elbow on the freak play.
Earlier in the game, Wacha made an outstanding heads-up play on a scorching liner off the bat of Diamondbacks third baseman Martin Prado:
"It hit a nerve, and the whole hand went numb. It was a pretty scary feeling, that's for sure," the right-hander said about his elbow. "I'm sure I'll have a little bruise there tomorrow."
The severity of the bruise hasn't yet been reported by the Cardinals.