Predatory in my opinion, the player was lying prone on his stomach, on the ice unable to defend himself and gets cross checked in the kidneys. At the minimum that is a fine. Stamkos punches an unwilling combatant, with his bare hand multiple times in the head area, are we protecting players brains or are we not? The League needs to take a tough stance against this predatory type of actions.
Well two good things happened there, 1) TB showed the Leafs they are scared of them, that they need to cheat to win and 2) the refs called the right PIM on Rielly.