Midway through the first period of a critical division game, Ryan Carter stuck out his leg and caught Zac Rinaldo in the knee. Rinaldo spun through the air and got up in pain, but he didn't miss any ice time.
Carter got a penalty for tripping on the play, which, based on the video, doesn't really seem to be the correct call. The NHL has a rule on the books for situations such as this:
50.1 Kneeing - Kneeing is the act of a player leading with his knee and in some cases extending his leg outwards to make contact with his opponent.
That's a perfect description of what Carter did, so "kneeing" would have been the right penalty to call. Whether the infraction warranted a minor, major, or possibly even a suspension is up to you. Carter just got the two minutes -- and the Flyers scored on the ensuing powerplay.
(Video from HockeyVideoHD)