I saw something on Sports Center about this and both of the coaches were making light of it in post-game press conference. One of them said that he's always taught his players to wrap up the other player when tackling.
They said it's just part of the game. ESPN even did a slo-mo analysis and illustrated that the ref tried to go into the gap between the two tacklers and the QB, but couldn't get away so he protected himself by lowering his shoulder.
It looked intentional to me, but the coaches are cool with it.