Of course Gronk was at Fenway Sunday night for the Paul McCartney show, and if Gronk's at the show, you know he's going to get on stage and get crazy, and that's just what he did.

He was on stage for 'Helter Skelter,' and he played a little air guitar, danced like a maniac and shouted into the mic. As always, it looked like he was having a blast.