The play occurred just one minute and 35 seconds into the game. After Los Angeles Kings forward Rasmus Kupari missed a Grade-A opportunity in the Kings' offensive zone, he swung around the net and made contact with Kampf's head near the bottom of the left face-off circle.
"It looked to me like direct contact to his head, obviously," Maple Leafs coach Sheldon Keefe said after the game, a 6-2 win. "So, I hate to see that. I don't know how much intent was there. It looked pretty accidental to me."
Beyond receiving contact to the side of his head, Kampf also fell hard to the ice on his left arm. Kupari was charged with a tripping minor for the collision.
The specific nature of what Kampf's injury may be is not known at this time. Kampf left the game and did not return, with the team describing his departure as being for "precautionary reasons."
Kampf, 26, has registered three goals and three assists through 20 games with the Maple Leafs this season while playing mostly on the third line. He signed a two-year, $3-million deal with the club last off-season after playing the first four seasons of his NHL career with the Chicago Blackhawks.