There was, however, little bruising and no numbness. Wacha played catch without issue at Busch Stadium prior to the Cardinals' series finale against the D-backs, clearing the way for him to make his next scheduled start, Monday's series opener against the Yankees.
"Everything feels good. I have all the range of motion and everything that I was looking for," Wacha said. "As far as I know, I'm on track. The arm feels great and I just have the normal soreness after pitching yesterday."
Wacha was taking his place on the bench in the bottom of the sixth inning Wednesday when a foul ball off the bat of teammate Matt Adams scorched into the dugout. He had little time to react and was unable to avoid the ball, which caused his right arm to go numb and forced St. Louis to go to the bullpen early.
Wacha has had quality starts in eight of 10 outings this season, but he only has three wins. Arizona took advantage of his early exit with Gerardo Parra's two-run homer off reliever Carlos Martinez in the eighth inning, erasing what would have been his fourth victory of the season. He settled for a no-decision in the Cardinals' 3-2 win in 12 innings.
"I think it scared him more than anything else," manager Mike Matheny said. "Fortunately it happened at the point of the game in which it did and we were able to get him out before he even had to go out and see what it felt like."
A day after the liner made his hand go numb for about 30 seconds, Wacha was feeling fortunate that seam marks were the only repercussion.
"It was definitely pretty scary. I've never had that feeling before," Wacha said. "Luckily that numbness went away and it feels normal right now."
Alex Halsted is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.