Vikings TE John Carlson injures knee at practice

Vikings TE John Carlson, one of the team’s prized free agents signed in the offseason, left Tuesday afternoon practice after injuring his knee.

Following practice, coach Leslie Frazier said Carlson had sprained his medial collateral ligament while blocking on a running play. Carlson was seen walking with a slight limp as he headed to the onfield training room.

Frazier said that Carlson didn't tear a knee ligament, but the injury could keep him out for a while. The Vikings' first preseason game is at San Francisco on Aug. 10, and that could be in jeopardy for Carlson.

"You don't have to have any surgery. It heals by itself," said Frazier. "It's a little bit more of a pain-tolerance thing and how he feels."

The Vikings offense favors two TE sets, so the injury is a blow to Carlson and the team. But the Vikings do have depth at the position with TEs Allen Reisner, second-year man Mickey Shuler and rookie Rhett Ellison.

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