Acuna, 24, had started Atlanta's previous 19 games. The three-time All-Star has appeared in 110 games overall since returning in late April after a torn right ACL ended his 2021 season.
"He had some back tightness right at the end of batting practice," Braves manager Brian Snitker said after Atlanta's 1-0 loss to the Philadelphia Phillies on Thursday night. "He was swinging in the cage a little bit and something banged on him and he wasn't available."
Acuna is day-to-day. He is hitting .270 with 13 homers, 46 RBIs and 28 stolen bases this season.
"We'll treat him up and we'll see if he's available tomorrow and ready to go," Snitker said. "He hadn't been dealing with that. It was just one of those things."
The Braves trailed the idle New York Mets by 1½ games in the NL East after Thursday night play with 12 games remaining. The teams have a three-game series in Atlanta next weekend.