"defenseless receiver" and all that, really limits how you play a guy going up for a catch. Williams should have waited for Diggs to land, turn, look upfield, compose himself, dust off his shoulder pads, and begin running forward before politely suggesting to Diggs that he roll - gently - to the ground, so he could be carefully tagged "down."

Seriously, I do think the DB there was concerned about drawing a flag of some type, got caught in two minds, and messed up.