Chicago Blackhawks defenceman Duncan Keith has been suspended one game for his high stick to the face of Los Angeles Kings forward Jeff Carter in Game 3 of the Western Conference Final.

Keith will sit out Game 4 on Thursday night as his team tries to extend their 2-1 series lead over Los Angeles.

In the NHL's suspension video it was noted that Keith is classified as a repeat offender, having served a five-game suspension at the end of the 2012 regular season for a hit to the head of Vancouver Canucks forward Daniel Sedin.

Keith clipped Carter during an exchange well behind the play in the second period of L.A's 3-1 victory. After Carter took a short hack at Keith's hand while the defenceman bent down to pick up his glove, Keith responded by skating behind Carter and hitting him in the face with a one-handed swing of his stick, dropping Carter to the ice.

"Yeah, it was accidental," Keith said after the game. "Obviously, I wanted to give him a tap, but not where I got him. I felt bad. I'm glad to see that he came back. It was just a scuffle. It was an accident."

The injury forced Carter, who wears a visor, to miss the Kings' ensuing four-minute power play.