Much virtual ink and vitriol has been spilled in criticizing the Vikings' choice to run a base Tampa 2 defense. This is despite the fact that simply having Tampa 2 as a base doesn't mean that a team will run it exclusively-or even for the majority of their defensive snaps. In order to effectively understand when a team is and is not running the Tampa 2, we must first know what the Tampa 2 really is and that is what this article is about.
This picture is a depiction of a defense running a 4-3 base with a Cover 2 shell. The only real difference between the standard Cover 2 and Tampa 2 is that the MLB is asked to cover a zone that extends 2-5 yards further down the field then the other linebackers. Both corners are responsible for the short routes on their side of the field and both safeties are responsible for a "deep half."
One of the architects of the Tampa 2, Tony Dungy, said that "Tampa 2" is merely a media name for a specific blend of defensive ideas and concepts. The first (and most obvious) is the Cover 2 shell. Dungy learned the Cover 2 when he played and was a coach for the Steelers and he even said that the majority of his concepts have been around since then (1977). In reality, the Tampa 2 had its beginnings in Minnesota in 1992 when both Monte Kiffin and Dungy were on the Vikings' staff. The second concept was added to the mix in Minnesota.
This second concept was the marriage of a "one gap" style that had been popular with the Vikings at that time. A two-gap style dictates that a defensive lineman engage the offensive lineman head-on and stalemate him while retaining the ability to tackle a ball carrier on either side of that lineman. The one gap style means that the lineman is only responsible for a single gap and the linebackers are responsible for the other gaps not filled by the linemen. The crucial part is that the one-gap scheme allows the defensive linemen to be smaller (since they're not engaging a lineman head on) and, therefore, quicker off the ball. This usually increased their ability to rush the passer-which is a core tenet of the Tampa 2.
To paraphrase a little more of Dungy's book "Quiet Strength" (which is also where I got a lot of the details I mentioned above): The traditional view is that the Cover 2 shell is the critical component of the Tampa 2. The reality is that the most critical parts are defensive line play and sound fundamentals in coverage. The Tampa 2 is based off of getting pressure on the quarterback while only rushing the four linemen. Defensive backs cannot cover every route in their zone without guessing and the pressure is supposed to remove or otherwise alleviate their requirement to guess. Dungy also did not want to rely on blitzes due to their "feast or famine" nature. This is, therefore, the last concept that is crucial of the Tampa 2: the ability to get consistent pressure while only rushing the four linemen. Although, in reality, any defense will be insanely potent if they manage to get pressure with only four rushers. How potent? Think of what the Giants did to the 18-0 2007 Patriots squad in the Super Bowl. They held the most potent offense at that moment of NFL history to 17 points because they could pressure Tom Brady with only their four defensive linemen.
I'll end this with an excerpt taken from Quiet Strength that details the main part of the Tampa 2 scheme. It is an interaction between Dungy and Rod Marinelli-the defensive line coach for the Bucs under Dungy.
During our first training camp in 1996, we were watching film as a staff, and Rod was particularly intrigued during the 7-on-7 drills. The 7-on-7 is a pure passing drill in which the linebackers and defensive backs work against the running backs and receivers. The linemen are usually on the other end of the field working on pass protection and rush. As a result, Rod never saw the 7-on-7 drills live. He kept stopping the film to ask the same basic questions after pass completions.
"How would you stop this one? Can you even cover that route? Won't they complete this pass all day?"
He loved my answer. "It all depends on the pass rush. We know there are holes in zone coverage if the quarterback has time to find them. But if he's under duress, he won't always see the open receiver, and he won't be able to hit him consistently."