Any time you punch someone without a challenge to a fight, in hockey that is considered a sucker punch. If every cross check in a hockey game was an invitation to turn around and punch someone, we would see it dozens of times per game and this thread wouldn't exist.
It's already been pointed out by numerous posters but many of you seem to be duped by the thread title and SJ broadcast in the clip into thinking Kostin was just innocently on his way to the bench before being cross checked. If you actually watch the full clip, he chicken wing elbows Vatrano in the side of the head on the way by, which more than earned a cross check in return. He threw a cheap shot, took a cross check in retaliation and then threw a sucker punch with no invitation to fight. Punk move on Kostin's part
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