Some prologue first, beginning with San Francisco's defense. It's legitimate. The 49ers against the run are downright belittling. In 2009, they allowed only 3.6 yards per carry. This season, including the game against the Saints, they've allowed only 2.7 yards per carry. Running the ball against them can be difficult, is what you'd say if you wanted a nice smack to the forehead.
What makes San Francisco so great on defense is a combination of a bend-don't-break mentality, instilled by coaches Mike Singletary and Greg Manusky, and the players they put on the field.
Patrick Willis is the best linebacker in the game, and probably the most physically gifted one too. Anyone who saw his pregame chat with Jon Gruden was quickly alerted to how hard Willis studies tape and prepares for games as well.
Lining up around the game's best linebacker is a very good defensive corps. Takeo Spikes plays the other inside linebacker in the 3-4. He's not as young as spry as he once was (a knee contusion suffered during Monday night doesn't help), but he still manages to raise a ruckus against offenses. Justin Smith makes a ton of tackles from defensive end. Nate Clements has made a career out of being a solid cover corner who is excellent playing the run.
But the defense's anchor is Aubrayo Franklin. Like Pittsburgh's Casey Hampton, he's a shorter defensive linemen, but that's what makes him perfectly suited to play nosetackle. At 6'1'' and 317 pounds, it takes a lot to get under his pads and get him moving anywhere but where he wants to go.
Franklin was a hold out this training camp. To know exactly how much he's worth to the 49ers, just look at what they paid to get him playing again: $7 million. That's a lot to pay for a 30 year old linemen, and by paying it the 49ers are showing he's worth it.
Against the pass, San Francisco is slightly worse off. It doesn't make them terrible, they're just not as good as they are against the run. In Week 1 at Seattle, the Seahawks rushed for just 13 yards in the first half and still lead by eight via a combination of passes, playaction, and turnovers. They'd still finish the game averaging just 3.3 yards a rush though.
The first Seattle touchdown came on a playaction pass that turned into Matt Hasselbeck sprinting for the corner pylon. He got there and put the Seahawks up 7-6. It would be all they needed to win the game, but it was just part of what New Orleans needed.
In the third quarter, up 21-6, Seattle smashed their way to the 49ers' 3-yard line. Instead of trying to run the ball, they aired it out, trying to circumvent San Francisco's run defense. Two incompletions had them staring at 3rd-and-goal. Their next play looked like this (for clarity I'm not showing the defense, but check the video out to see how they line up):
Seattle has Matt Hasselbeck step back into Shotgun. The offense then uses a Bunch formation right while isolating Deion Branch wide left. Hasselbeck throws the fade into the corner of the endzone; Branch makes the catch and Seattle goes up 28-6. By now the Niners are cooked, but someone else is watching.
Cut to Monday night (first quarter), and the Saints have arrived in San Francisco's red zone. Already up 2-0 from the errant snap-turned-safety, New Orleans hands off to Pierre Thomas who goes for three yards to the 49ers' six. On second down, they line up in something resembling Seattle's red zone plan:
It looks similar to Seattle's iso play, but with a few wrinkles. The running back is moved to the other side, and more importantly, since it's Reggie Bush, he's running a choice route instead of a flare to the sideline. Finally, the tight end comes in to block.
What happens is that the 49ers react the exact same way they did against Seattle, but do a much better job of covering the iso receiver. During the play he (the lone receiver split wide) finds himself double covered, and Drew Brees checks down. In the video you can actually see Brees' eyes switch from the right receiver to Bush as he comes open.
The intention was to hit the fade in the endzone like the Seahawks did, but when he's covered Brees improvises. He sees Reggie Bush cut back inside, scorching Patrick Willis, and hits him in stride for the score. 9-0 Saints.
Now here comes the devious part.
In the third quarter, down 14-9, New Orleans found itself back in San Fran's red zone. Their game plan doesn't change much. Instead of trying to run the ball (they were on the three-yard line), they go right back into their Shotgun Bunch formation. Except now, Reggie Bush motions from his spot beside the quarterback and widens out past the iso receiver before the snap. After having been touched up by Bush last time, Patrick Willis follows him.
The iso receiver runs his usually route, as do two of the receivers in the bunch. David Thomas though, at tight end, hesitates like he's going to stay in and block, like he did last time. Then he chips off the defensive end and runs the same choice route Bush ran in the first quarter. This play though, it's all deliberate. Brees feints a little by looking to Bush and the iso receiver, but then turns and drills Thomas for the touchdown.
Sean Payton isn't a stupid guy. He knows all about the 49ers defense and what they do well. That's why he followed Seattle's lead and spread them out in the red zone. And, when the Saints tried to get tough with them and grind out a touchdown in the fourth quarter, Heath Evans got stuffed on the goal line. New Orleans realized why they'd avoided trying to run the ball in the first place.
Using what Seattle had shown them previously, the Saints found ways to score against San Francisco. It's a little look into the intricacies that win football games. Or, a very good coincidence.
Either way, Matt Cassell and the Kansas City Chiefs might want to think about copying this coincidence.