DETROIT -- Pittsburgh Penguins defenseman Kris Letang was placed on injured reserve Monday, after twice leaving a game against the Detroit Red Wings on Saturday night after appearing to injure his left knee.
Penguins coach Mike Sullivan said Letang is week-to-week with a lower-body injury.
Letang got tangled up with Detroit's Thomas Vanek early in the first period of Pittsburgh's 6-3 loss and twisted awkwardly on his way down to the ice. He got up slowly and tried to keep weight off his left skate as he went toward the dressing room.
Letang returned briefly later in the first, but he left again and didn't return, finishing with just 2:06 of total ice time.
Letang scored 27 seconds into the game for his fourth goal and 23rd point in 30 games this season.
Letang missed seven games with a lower-body injury and five games with an upper-body injury earlier this season, so playing without him will be nothing new if he misses any time.
"He's our top defenseman, but we've done it before," Sullivan said after the game. "We've got capable people. It won't be one guy -- it'll be by committee. Let's not get ahead of ourselves. We'll see how he is."
The Penguins recalled Jake Guentzel -- the organization's top prospect -- and Chad Ruhwedel from Wilkes-Barre/Scranton of the American Hockey League.
ESPN's Craig Custance, The Associated Press and the Pittsburgh Post-Gazette contributed to this report.