big on big
also: BOB · big-on-big · back on backer · man protection
A pass protection where the five linemen take the down defenders and the back takes a linebacker. The first protection most coaches install, and the one that depends most on getting its count right before the snap.
big on big, the pass protection
A pass protection whose rule is in its name: the big people block the big people. The five offensive linemen take the down defenders and a running back takes a linebacker.
The count is declared before the snap. The quarterback or the center names a linebacker as the Mike, and that one word settles the only question the protection has: which second-level defender belongs to the line, and which belongs to the back.
The rest falls out of alignment. A lineman with a defender on him has that defender, which accounts for the whole front. Whoever is left over climbs to the Mike, and the back takes the other linebacker. In the drawing above, the guards and tackles are all covered and the center is not, which is why he is the one going to a linebacker five yards away.
The declared Mike does not have to be the man the defense calls its middle linebacker; for the offense the name is bookkeeping. If the back's linebacker rushes, the back blocks him. If he drops, the back can release into a route once he has confirmed the man is not coming, which is a check release.
Its virtue is that it is teachable in a day and every blocker knows exactly who he has. Its cost is that it is a plan, and a plan assumes the defense stays where it aligned.
Being outnumbered and being wrong are different failures, and coaches conflate them. Six blockers against six rushers has the bodies, so a free rusher there means the count or the communication broke and blocking better would not have saved it. Six blockers against seven cannot be blocked at all, and the answer is a hot throw rather than a fix up front.
BOB, back on backer, man protectionslide protectionA note on how the term is used
Big on big protects people and a slide protects gaps, which is the whole difference in one line. Most teams run a hybrid, sliding one side and playing man on the other, so asking which side is sliding is usually more informative than asking what the protection is called.
Where you will hear it
- universal, and the standard first protection installed at most levels
By level
The right first protection at youth and lower high school level for the reason above: everybody knows who he has, and defenses there blitz from fewer places. Higher up the hard part stops being the first matchup and becomes what happens after it, which is why most offenses end up combining big-on-big rules with slide rules rather than playing man across the whole line.