I don't believe he was "toppling backwards".  I think Harris hit his arm as he threw.  He might have been hindered in his ability to step through by the guy who just beat Morse being in his face.  I'd need to see an angle other than the broadcast film to be sure.    Was there an element of "hero ball" in there? Probably.    Edit: here's the little animation they put up in Gamepass, paused just before the ball is released   Question for people who know more than I