"He hit a double and felt it a little bit in his quad and for precautionary reasons we went ahead and pulled him out of the game," Porter said after his team's 10-3 loss.
Springer, playing in his third rehab game, doubled in the first inning and walked in the fourth while starting at designed hitter against Burlington. He was lifted for a pinch-hitter in the fifth inning. Porter said earlier in the day Springer was scheduled to play seven innings in the field, so it's unclear why he was at DH.
"We're all behind him and we want the best for him," said Astros first baseman Jon Singleton, who, like Springer, made a much-anticipated debut this year. "If he doesn't come back, we'll make the most of it. We're definitely hoping he makes it through."
Springer started in right field for the first time Tuesday for Quad Cities and was 0-for-2 after serving as designated hitter on Monday in his first rehab game.
"We'll have a good indication of how he recovered from back to back days [in the field] and we'll be able to make a decision from there," Porter said prior to Wednesday's game. "Maybe we'll have him off Thursday and have him ready to go on Friday."
Springer was hitting .231 with 20 homers and 51 RBIs in 78 games since being called up in the middle of April. He was the American League Rookie of the Month in May.
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.