Toronto goaltender Jonathan Bernier has a groin strain and is "believed to be day to day," the Maple Leafs said Monday.
The team posted an update on Bernier from coach Randy Carlyle on its Twitter account.
The injury was revealed when Bernier underwent an MRI earlier Monday.
Bernier left Thursday's game against the Los Angeles Kings and was replaced by James Reimer, who stopped every shot he faced to pick up the 3-2 victory.
Bernier has a 25-16-7 record with a 2.64 goals-against average, a .925 save percentage and a shutout in his first season with Toronto.