Philadelphia's Jakub Voracek skated directly into a Kronwall, which, from the point of view of physics, isn't much different from skating into a brick wall. Voracek was clearly out for a few seconds, going directly into the always-terrifying the fencing response. No penalty was called on the play, and it's unlikely that the Shanaban will come calling, but damn. That was just straight-up destruction.
Voracek took stitches in his lip, and the Flyers say he will be re-evaluated today. But remember: whether stitches or grade III concussion that plagues player with dizziness and headaches for the rest of his life—it's all just an "upper body injury."