In reply to: What’s a wham, please? * posted by 84david
the DL is taught that when his OL blocks inside to flip his head inside and lock for an OL trapping him. The last thing that he's looking for is an H back or a fullback trapping him.
It's a very effective play and it also can make the DL hesitant on trap as well. Can also just run it on power if you leave the end man on the line of scrimmage unblocked by the OL and lead on him with a fullback from the backfield.
My favorite part was when I made the cut that helped set it up. I'd be running into the hole and the tackler thinks they have me dead to rights when I put my foot down for the cut, the trap/wham guy hits him and I cut right out of the block/tackle and out to the next level, which often meant an undersized, underclassman safety for a trucking target. Most of the best runs of my career (including my last one ever) were trap plays.