Believe it or not, Buffalo Bills fans: we've already seen our favorite team use defensive ideas from Mike Pettine in a regular season football game, even though the Bills have yet to play a regular season game with Pettine as the defensive coordinator.
Flash back to Week 4 of last season (briefly, I promise): the New England Patriots racked up a nauseating 580 yards of offense and 52 points in a throttling of the Bills at Ralph Wilson Stadium. The two teams met in Week 10, and then-defensive coordinator Dave Wannstedt had his troops doing some different things in a much better (read: still pretty bad in many ways) road performance that the Bills lost by six points. New England gained a fairly pedestrian 347 yards of offense that day, and the Bills had a chance to win the game in the final minute.
Here's one example of a tweak that Wannstedt made in that Week 10 loss: he started using Mario Williams at defensive tackle on third downs, with Kyle Williams standing up behind him. The two rushers gave the Pats some problems right up the middle out of this look, and the Bills also used the front to pressure different gaps throughout the day.
Where did Wannstedt, one of the most schematically-conservative coaches in the NFL last season, come up with this wrinkle? There's a good chance he saw Pettine and the New York Jets do the same thing with Muhammad Wilkerson three weeks prior in a 29-26 overtime loss to the Patriots in Foxboro:
Wannstedt even expanded on the idea a bit, lining both Kyle Williams and Marcell Dareus up over the center standing up and letting them wreak havoc; on one play in particular, Dareus destroyed a double team with a running start and Williams spun around the left guard to record a pressure on Brady.
Here's another package that Wannstedt copied from Pettine: Alex Carrington lined up on the nose with a Williams at each three-tech spot. It's a scheme that the Jets used with success in Week 7, as well - and, in fact, the Jets spent a lot of time with two three-techs on the field in obvious passing situations.
While the Bills borrowed looks from the Jets, there were some key differences in execution. Buffalo's pressures were not as varied, even as they were using new fronts; the Jets brought pressure from different directions, overloaded gaps and even dropped out into coverage with a three-man rush, while the Bills were a little easier to diagnose. Buffalo actually had a bit more success rushing the passer, however, but both teams were able to put a dent in Brady's efficiency.
One look that the Bills didn't use, but that the Jets used a lot on third downs, was a linebacker-heavy front that featured two inside linebackers pressuring the A gaps. Again, the Jets would run games inside with the two 'backers and two tackles, send both linebackers into one gap on delays, or drop out of the look into coverage. You should expect to see this look when Pettine and the Bills take on the Patriots this Sunday. (Note in the third still, also, that a second inside linebacker over the right guard is replaced by a third safety in the same front; you can expect to see Da'Norris Searcy lined up and blitzing quite a bit against Brady - which, yes, Wannstedt had him doing a bit last season.)
Brady won both of these games and put up very good performances in both contests. Against the Jets, he was 26-of-42 for 259 yards with two touchdowns and no picks; the production was remarkably similar against Buffalo three weeks later (23-38, 237, two touchdowns, no picks). What we saw, however, was a Brady that was less efficient than when he's firing on all cylinders: many of Brady's opponents would take a game in which he threw 15-16 incomplete passes, simply to better their odds of forcing him into mistakes. The Bills, for example, had a couple of opportunities for tipped-ball interceptions in Week 10 that they couldn't capitalize on.
The book on Brady is simple: pressure him up the middle (note each team's focus on the A gaps in particular), vary your fronts and coverages, make him less efficient and hope it leads to a few turnovers. We've already seen a previous version of the Bills borrow from the Pettine playbook to achieve those goals; now we'll get to see the man himself execute his game plan on Sunday.