They will be placing the outfielder on the disabled list, and he will be re-evaluated in 10 days.
The rookie injured himself while attempting to beat out an infield single during Sunday's game against the Boston Red Sox, as his leg buckled as he hit first base before he tumbled to the ground. The injury looked bad, to the point there was legitimate concern he may have torn his ACL.
Monday's news, then, was a welcome relief for Atlanta.
"It's definitely scary whenever you see a teammate go down the way he did," shortstop Dansby Swanson said, per ESPN.com. "We're definitely thankful that he was able to walk off. I think he'll bounce back just fine. It's just a matter of when."
Acuna, 20, is hitting .265 with five homers, 13 RBI and 19 runs in 29 games this season. He's provided a spark for the Braves at the top of the order, alongside Ozzie Albies, and his strong play has been a major factor in Atlanta's surprising 30-21 record this season.
With Acuna out of action, Preston Tucker will likely take over the left field duties.