Nolan Patrick, the Flyers' second-line center, will miss seven to 10 days because of what general manager Ron Hextall on Thursday called an upper-body injury.
In the first period of the Flyers' 7-4 win Wednesday in Ottawa, Patrick got hit in the face with a stick and later got crunched into the boards by Mark Stone and left the ice.
Patrick was sidelined for a short time last year with a concussion.
Based on Hextall's timetable, Patrick will miss two to four games.
Patrick, 20, the No. 2 overall pick in the 2017 draft, finished strongly in the second half of last season. He has no points and is minus-5 in four games this season and did not score during the preseason.
The injury might give Jordan Weal a chance to get back into the lineup. The Flyers could also move Scott Laughton back to center, but he has played well at left wing and the team may be reluctant to shift him.
The Flyers will face Vegas in a Saturday matinee at the Wells Fargo Center.