CLEARWATER, Fla. -- Philadelphia Phillies first baseman Rhys Hoskins needs surgery for a torn ACL after injuring his left knee Thursday fielding a grounder in a spring training game and is expected to miss a significant amount of time.

The Phillies did not say when Hoskins would have the surgery or exactly how long the slugging first baseman might be sidelined.

Hoskins hit 30 homers with 79 RBIs last season for the reigning National League champions.

He was backing up to play a chopper on Thursday when the ball popped out of his glove. Soon after, he fell to the ground and clutched his left knee. Teammates gathered around him before he was taken off of the field.

Hoskins, a free agent at the end of the season who turned 30 last week, hit six homers in Philadelphia's playoff run last season. The Phillies lost to the Houston Astros in the World Series.

The injury was another blow for the Phillies, who will be without top pitching prospect Andrew Painter for another few weeks because of a sprained ligament in his right elbow. And slugger Bryce Harper isn't expected back until around the All-Star break after undergoing Tommy John surgery in November.