 They want to get "Knock back" by reestablishing the line of scrimmage in the opponents backfield and not get pushed back into his linebackers.If a running play comes through one of those gaps, he must make the tackle or control what is called the "jump-through"—the guard or center who is trying to get out to the linebackers.The ideal nose tackle has to be much bigger than 4–3 DTs, weighing around 335 pounds or more.