It all begins with what appears to be an illegal subsitution, and there's some movement on the line, but the end result is a super-impressive touchdown run.
There's really little mystery here with the playcalling.
It's a straight sweep, perhaps even a broken play. The defense has some pretty good penetration, and the running back doesn't really seem interested in carrying out the fake, instead opting to completely stop running when faced with the prospect of getting hit.
But our heroic little quarterback -- undeterred by the tomfoolery -- destroys the middle linebacker, then makes a move on the sideline that would make Southern Cal era Reggie Bush proud.
Then comes a mostly-unnecessary downfield stiff arm followed by a completely unnecessary block in the back, but then, paydirt!