When it comes to hockey, there's nowhere to hide on the ice. NHL referee Kelly Sutherland got a harsh reminder of that fact Thursday night.

The veteran referee was at the center of a scary scene in a game between the Los Angeles Kings and Toronto Maple Leafs. Kings defenseman Jake Muzzin came skating through the zone along the boards, which is where he caught Sutherland with a nasty-looking (accidental) blow to the head.

The hit happened in the final seconds of the first period. Sutherland was helped off the ice and his night looked to be over. For better or worse, however, Sutherland proved the players aren't the only tough guys on skates, as he was back on the ice for the start of the second period.

H/t to CBS' Eye on Hockey