Toronto Maple Leafs starting goalie Frederik Andersen returned to practice today following a mysterious exit from Saturday's loss in Buffalo, but his time on the ice was short as he left the workout after about 20 minutes.

Andersen was removed from the 5-2 defeat to the Sabres after one period, the result of an apparent upper-body injury.

It was unclear what exactly prompted the 27-year-old's exit from Saturday's game.

Leafs coach Mike Babcock said Saturday only that "the other team's doctor thought he should come out of the game, so he came out of the game."

There was also no immediate word about why he left practice early.

Andersen was one of three goaltenders on the ice today, joined by backup Curtis McElhinney and Garret Sparks, who was recalled on emergency basis from the Toronto Marlies.

McElhinney gave up three goals on 22 shots in Andersen's place against the Sabres and will occupy the starting role if Andersen is out any length of time.

Toronto's next game is Tuesday night against the Florida Panthers.

Acquired off waivers from Columbus, the 33-year-old has a .919 save percentage in 10 games with the Leafs.

"I'll just prepare the same way that I've been doing all year long," McElhinney told reporters on Saturday. "It's a good opportunity regardless of what happens with Fred right now so, you know, just go in and get a couple days of practice and get ready."

Finnish prospect Kasperi Kapanen was also an unexpected participant in the Monday practice at Mastercard Centre, perhaps due to find a role with injuries plaguing Toronto's fourth line. Kapanen has 18 goals and 43 points in 43 games for the AHL's Toronto Marlies this season.

Toronto enters Monday's action holding onto third in the Atlantic division, one point up on Boston with a game in hand.