Washington Capitals right wing T.J. Oshie left with a noncontact injury in the third period of a 5-3 win at the Tampa Bay Lightning on Thursday night.
Oshie went down to the ice after making a move near the offensive blue line. He crawled along the boards to the bench and needed assistance back to the locker room.
Capitals coach Spencer Carbery said there is a "fairly high" level of concern about Oshie's injury.
"We'll evaluate more [Friday], but it's never a good sign when you see a player leaving the ice like that," Carbery said.
On social media after the game, Oshie posted: "I'll be back. Thanks for the love caps fans. #NoBadDays"
The Capitals (26-21-8) moved within five points of the Lightning (30-23-5) for the final playoff spot in the Eastern Conference.
The Associated Press contributed to this report.