Saints - Buccaneers: What happened to the Bucs' pass rush?

On Sunday, New Orleans quarterback Drew Brees gashed the Tampa Bay Buccaneers to the tune of 377 yards and four touchdowns. And yet, the Bucs had the Saints in the perfect situation early in the game. They jumped out to a 14-0 lead and forced the Saints to become one-dimensional (they had just 13 called rushes versus 26 called passes in the first half). This allowed the defensive line to play the way they want to play: rushing the quarterback, getting off quickly and

The result: no sacks. In fact, the Buccaneers didn't even get Brees on the ground once - there simply wasn't much pressure on the veteran quarterback. So, what happened? Why did a defensive line that destroyed the Cowboys' and Panthers' defensive line and has been incredibly stout against the run suddenly disappear against the New Orleans Saints and, to a lesser extent, against the Washington Redskins and Kansas City Chiefs? What has changed?

After watching the game again, I have a few reasons why this didn't happen, who's to blame, and why this is a concern going into the future.

1. The defensive line had a bad game.
   This is the number one problem: they simply didn't play all that well. Gerald McCoy wasn't as explosive as he had been in previous games, Michael Bennett was held in check while Daniel Te'o-Nesheim was almost completely invisible. This is a concern going into the future, and Te'o-Nesheim's performance is the most troubling. The right defensive end was going up against a weak offensive tackle, one that the Bucs have victimized repeatedly in the past, and Bushrod held him in check on all but one play throughout the game.
   
   This kind of execution by players will get you killed against a veteran quarterback like Drew Brees.
2. Horribly executed stunts
   The Tampa Bay Buccaneers love stunts and games on the defensive line. They love to send a defensive tackle around the offensive tackle and have a defensive end loop inside. That's all well and good, but doing that presents you with two problems: it means the defensive tackle has basically no chance to get to the quarterback, and stunts take time to develop. The Bucs' best defensive lineman by a considerable length is Gerald McCoy - yet when he's asked to stunt, he won't affect the play. And when the defensive end then just goes inside immediately, well, he doesn't have a chance either - the offensive guard and tackle can easily exchange responsibilities. This is called 'setting yourself up for failure'. It is not a good look.
   
   This is amazing in part because the Bucs have been incredibly awful at these stunts for about four seasons now. Five different defensive line coaches have come and gone, and they even have a front-seven coach now - and none of them can teach a variety of players how to run these stunts. Is there something in the water at One Buc Place that attacks that specific part of a defensive lineman's brain? I'd advise the Bucs to just dump these stunts wholesale because THEY DO NOT WORK.
3. The Saints have good players and good schemes
   The New Orleans Saints may not have the best offensive tackles, but their interior defensive line is really good: Jahri Evans is one of the best guards in the NFL, while Ben Grubbs isn't all that far behind and Brian De La Puente is a surprisingly solid center. Considering the fact that Gerald McCoy is the Bucs' only real threat as an inside pass rusher (although Bennett could move from his DE spot inside and so some damage too), it's no surprise that the inside push was mostly lacking. Having three players to hold in check one good pass rusher will usually do the trick - although this was far from McCoy's best day.
   
   Jermon Bushrod and Zach Strief at tackle are the weak points, but the Saints do a lot to help these two. They chipped defensive ends with releasing tight ends and running backs, kept in extra blockers, used slide protection to help out a specific tackle, used roll-outs to get Brees away from the pass rush. Plus, Brees is very good at stepping up into the pocket. The Bucs did take away that option fairly regularly with their push up the middle, affecting the throw that led to an interception and the subsequent three-and-out for instance, but it's still hard to get pressure on Brees.The Saints also tried to take away some of the defensive line's aggression with screens, draws and delayed handoffs with mixed success.
4. Coverage was absolutely terrible
   This was one of the worst defensive games I've seen a while, looking at pass defense. Quite often, the defensive line had no shot of getting to Brees simply because the ball would be out of his hand in three seconds - coverage was not holding up. At times players were simply beat, especially Brandon McDonald who had no shot against Lance Moore. At other times, players completely messed up the coverage, giving Brees easy completions.
5. The three-man rush
   This was especially surprising because the Bucs used three-man rushes quite a bit. The idea behind a three-man rush is, of course, to beef up your coverage so that the opposing quarterback won't find that open player. But time and again, Brees would have time in the pocket against a three-man rush and find some massive, massive holes in coverage. I don't care if you have three Reggie Whites on your defensive line, you're not going to beat a good offensive line rushing three players with any kind of regularity. It gets a lot harder when your coverage still can't hold up.

Is this a concern for the rest of the season? In one word: yes. Gerald McCoy and Michael Bennett started the season in dominant fashion, combining for seven sacks through three games. Since then: nada. Some of that has been the way they've been used, functioning mostly as run-stoppers against the run-oriented Redskins and Chiefs, for instance - but part of it is that they're simply not playing as well as they were through the first four games. The imminent return of Da'Quan Bowers should help a little, but let's not forget that Bowers was far from dominant last season: he was incredibly raw, even for a rookie.

Another issue that won't go away any time soon: terrible coverage. This should improve once Aqib Talib gets back, and the Bucs should get better in coverage as they learn how to operate within this scheme: a lot of the problems aren't talent-related, but they're busts in coverage. Yet overall, this back seven isn't great and will get beat by good quarterbacks too quickly.

A lot of the other issues have to do with coaching, though, and I believe you'll see a lot more pressure if the Bucs simply stop doing the stupid things that don't work. No more three-man rush. No more absolutely terribly executed stunts on the defensive line. The question is: can the coaches stop calling that stuff?