Making the start in center field, Schumaker ran into the outfield wall when Pittsburgh's Alex Presley drove a 1-0 pitch in the first inning. Schumaker missed the ball on a leaping attempt, and Presley raced home for an inside-the-park home run.
Schumaker tumbled to the ground after hitting the wall and, unable to catch his breath, didn't get up for several seconds. The point of impact was of concern, too. It was Schumaker's rib cage that took the brunt of the hit, the same rib cage that had been hurt when he suffered an oblique strain last month.
"I don't think that was the debut I was looking for," Schumaker said. "First of all, I should have caught the ball. The problem was I couldn't breathe. Having an oblique injury, coming off of that and getting your rib cage rattled wasn't exactly what you wanted to do."
Knowing he shouldn't, Schumaker lobbied to stay in the game. Manager Mike Matheny watched Schumaker make a few throws and then told him to follow him back to the dugout. Schumaker was replaced by Erik Komatsu.
Matheny was upset with himself last month when he ignored his instinct and let Schumaker finish an at-bat. One swing after Schumaker insisted he was OK, he suffered the oblique strain.
Matheny wasn't going to take any chances a second time.
"He's going to say what most guys say in that situation, which is that they don't want to come out of the game," Matheny said. "I didn't believe him. Nobody wants to come out of a game like that, and nobody really wants to pull somebody out of a game. But all I could think of was being a little more tender and not be able to localize it, and then go up and take a big swing and watch what we did in Spring Training all over again. I'm not going to let it happen again like that."
The good news is that there doesn't appear to be a recurrence of the old injury. Schumaker said after Friday's 4-1 win that he expects to be cleared to play this weekend.
"I should be all right," he said. "I don't anticipate it being any worse [on Saturday]. Hopefully it's not a huge deal."
The cruel bit of irony is that Schumaker was starting in center only because Jon Jay was out with a sprained right shoulder. Jay sustained his injury on Thursday when he, too, ran into the wall while chasing a ball that ended up clearing the fence. He left that game early.
"It does seem to come in bunches," Matheny said of the pileup of recent injuries. "That's just how the game goes."
Schumaker wasn't initially expected to rejoin the team this quickly, but his rehab assignment was hastened because of an injury to Lance Berkman. Schumaker played in just four Triple-A games, and it wasn't until Thursday that he played a full nine innings. Had the rehab timetable not been shortened, Schumaker estimated that he would have played about five more Minor League games before rejoining the big league club.
"In a perfect world, would you want more [time]? Yeah, of course," Schumaker said prior to Friday's series opener. "But I wouldn't tell them that I could come if I didn't feel like I could help us."
The initial desire to stretch out the rehab stint came from Schumaker, who remembered the struggles he had last year when he hurried through a rehab assignment. But he was encouraged by how his timing -- both hitting and tracking balls on defense -- felt during his last two rehab games this week. That left him confident enough to tell general manager John Mozeliak that he was good to go.
"You always go in with a game plan, but that's not always how it works out," Schumaker said. "I wouldn't tell them I was ready if I wasn't OK to play."
Though there was no easing Schumaker back in on Friday, Matheny is expected to be generous with days off for Schumaker in the early going. Those four rehab games marked the only playing time Schumaker has had since March 16, the day he suffered the right oblique strain.
"We'll see how he's feeling and how he's doing," Matheny said. "Now are we going to throw him out there every day? I wouldn't say that. But we wouldn't have brought him if we weren't ready to throw him in there."
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.