I know everyone wants to be level headed and not seem like a rabid homer but as far as I'm concerned Perry hung his knee. Clear when you see it from the back angle. He sees John down and doesn't make an attempt to lift that left leg. Sure, he looked like a ghost after - like someone immediately regretting the action he just took might.
Funny its always the goons making these borderline plays that everyone jumps out to defend: Cooke on Karlsson, Tkachuck on Scheif, Perry on Tavares. These guys conceal it better than anyone. No one wants to believe they'd do it, as if humans are infalliable, especially when the stakes are high and adrenaline is pumping. Stupid, impulsive decision by Perry that I'm sure he currently hates himself for.
If you can watch the replay from our zone cam in slow motion a few times and tell me he didn't hang his knee I've got a bridge to sell you. Glad it doesn't seem like a career ending injury right now. Prayers to John and his family.