Coach Adam Oates said Thursday that Ovechkin would not make the trip for the game against the Philadelphia Flyers.
Ovechkin was hurt when he crashed head-first into the goalie and net early in the first period of Monday's loss to the Vancouver Canucks.
The Capitals have not revealed any details of Ovechkin's injury, other to say it is not a concussion.
Oates said there's "maybe" a chance Ovechkin will play in Saturday's home game against the Florida Panthers.
Ovechkin has scored 10 goals, second in the league through Wednesday's games.