Campbell was checked by Alex Ovechkin into the end boards behind the Hawks' goal with 7:44 remaining in the first period. Campbell remained on the ice for several minutes as trainers attended to him before leaving.
Ovechkin was given a five-minute major penalty and a game misconduct. The Capitals won the game 4-3 in overtime.
After the game, Hawks coach Joel Quenneville said, "[Campbell] is going to be out for a bit. It was a tough hit, a dangerous hit."