Elliotte Friedman of Hockey Night in Canada reports senior vice-president of player safety Brendan Shanahan has decided Cooke's hit-from-behind on Boston defenceman Adam McQuaid does not warrant further discipline.
The Pittsburgh left-winger was given a five-minute major and a game misconduct for the hit, early in the second period of Boston's 3-0 win in Game 1 of the Eastern Conference final on Saturday.
McQuaid, who was checked behind his own net, left the ice after the incident. He later returned to the game, one marked by chippy play and a similar hit by Brad Marchand of the Bruins on James Neal of the Penguins. Marchand was given only a two-minute minor penalty for boarding.
"It's a great relief because I want to be out there on the ice helping this team, not sitting in this dressing room worrying about winning or losing. I've been in that situation before and it's no fun. I'm just thankful I can go tomorrow night," said Cooke, who has tried to reform his ways since he was suspended for the last 10 games of the 2010-11 regular season and the first round of the playoffs after he elbowed New York Rangers defenceman Ryan McDonagh in the head in a March 2011 game.
"I chipped the puck in early, just after the red line. I had quite a bit of interference run from [Bruins defenceman Torey] Krug, which pushed me inside. But after I got by [Krug], I see [McQuaid's] right shoulder and he looks me right in the eyes.
"I think at the last minute he goes to make a reverse with the puck, but I already had committed to hit him. I don't drive him through the boards. I make contact. I think it's a penalty, but I don't think it's an ejection or a suspension. But that's my opinion."
Cooke is already reviled in Boston for a blindside head shot on Bruins centre Marc Savard in March 2010. He wasn't punished for that hit either, although the league did respond with a new rule addressing hits to the head.
Cooke has noticeably toned down his play in the last two years.
He also escaped punishment for an encounter this season with Ottawa Senators defenceman Erik Karlsson that saw Cooke's skate slice into Karlsson's Achilles tendon, sidelining the Ottawa star for 10 weeks.
The league felt that was an accident on Cooke's part.