I'm trying to figure out what happened there, did the one leg hit the apron and cause it to go flying?

Looks like the top leg caught masked guy in the elbow. 

 

Ow. 

I think it's the bottom leg to the lat. I see mat between the top leg and him and his elbow doesn't really come up until after he gets hit and the chair's already flying away by then. Also I think I watched it for way too long, far too intently because I swear I see his lat throb when he swings around the post at the end. Like, it totally comes out his arm hole and goes bloop bloop.

I'm trying to figure out what happened there, did the one leg hit the apron and cause it to go flying?

 

Time Travelling Archibald Peck actually caused a vortex to appear above the ring that sucked the chair away.

Michigan State locker room, post Rose Bowl victory. Noted smark haven.