I'd play him for a fool.
I'd be all "Hey Rex, I've got some Tootsie Pops in my bag but I forgot it in the locker room."
He would respond with eager giddiness, "My man, I will go get them if I can have some!", to which I will agree.
However, as he believes he's entering the locker room, he's actually entering a scale replica of it that is really a cage designed to trap him. I then agree to let him go and give him Tootsie Pops if he takes off all his pads (not what you think, hold on.)
Little does Rex know that I'm actually tricking him and won't let him go at all, but I put on his gear for my chance at Husker glory on the field.