"You make one weird move and it takes your breath away," said Wong, who was replaced at second base by Greg Garcia. "I didn't want to get taken out of the game, but there comes a point when you've got to accept the fact that you're not going to help the team."
Wong left the club during its last road trip and ended up missing five games while trying to address the tightness with treatment. But the discomfort never completely went away, Wong acknowledged. He tried to return for Friday's series opener after sitting again on Thursday.
Manager Mike Matheny could see that Wong was too compromised to continue playing after watching how gingerly Wong ran as he scored from second on a fifth-inning single.
"It wasn't right," Matheny said. "I had to get him out of the game. He wanted to stay in -- like every player does at this time of the year. But you can't risk a guy who can't move like he needs to."
Wong has been pestered by injuries throughout the season. Prior to the issues with his back, he spent time on the disabled list for a left elbow strain and a strained right triceps.
"Right now, in the thick of things, to have this injury come up, you just don't want that," Wong said. "We kind of thought we had it under [control] the first time. But [with it] coming back again, you've got to figure out what's wrong."
Jenifer Langosch has covered the Cardinals for MLB.com since 2012, and previously covered the Pirates from 2007-11. Follow her on Twitter and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.