There are 6 gaps. You have 3 or 4 men on the line. Nearly everyone should have to cover 2 gaps. Especially when there are 3 down linemen. At least in my mind.
Originally Posted by: wpr
Not quite because you also have to factor in the LBers. When they see a run they also have gaps to fill and/or tackle the guy if they try to go though those gaps. So it's 7 guys (8 if you count the SS) trying to fill 6 gaps BUT the offense knows where the ball is going, they can have lead blocker like a FB and they could pass the ball so you can't just assume it's a run play or they'll run a fake a player will bite on the fake and won't be in the right place in coverage.
If you're playing one gap then your more attacking the blocking and trying to beat the blocking by trying to get by getting up field and to the person with the ball. Like Raji beating the OG to get to the RB in the back field.
If you're playing two gap then your more trying to clog up the running lanes not letting the RB have a hole to run though and protecting the guys behind you from letting blockers get to them... so basically it's a role player position filling the holes with not only their bodies but trying to stop the blockers from getting out of the holes they're trying to make as well as keeping the blockers off the LBers to they can go make plays.
Also 3-4 DEs can be one or two gap depending on the system. Different systems ask them to do different things. The Packers system ask it's 3-4 DEs to play one gap while the Patriots system ask them to be more two gap players. Also it's very rare but "NTs" can be asked to be one gap players as well. Such case has been in Dallas' Jay Ratliff. Ratliff is a one gap player at NT. And that's why is pass rush numbers are so much better than other NTs, because they're playing two gap. (which makes me say Ratliff isn't a true NT because IMO true NTs are good at playing two gap, and Ratliff isn't) Almost all other NTs play two gap. Raji did in the 3-4 but played one gap in the 2-4 nickel. I think he's better at one gap but Raji can play ether well.