When the defenses for the San Diego Chargers and Indianapolis Colts take their turns on the field Saturday night at Qualcomm Stadium, they'll deal with more than the ordinary stress that goes into trying to stop an NFL offense.
For the Chargers, stress will go by the name of Peyton Manning, who on Friday was selected as the league's Most Valuable Player for the third time in his career.
For the Colts, its moniker will be Philip Rivers, who led the NFL in passer rating and touchdown throws.
Manning and Rivers are squaring off in an AFC Wild Card Game, but you'd be hard pressed to come up with a better marquee quarterback matchup if the conference championship were on the line.
"The challenge is tremendous because the guy is probably one of the best ever," Chargers defensive coordinator Ron Rivera said of facing Manning. "The other thing that makes it unique is he's got such good talent around him. His receiving corps is just about as good as any in the league, and I think his offensive line is playing very well right now."
Riding a nine-game winning streak, Manning and the Colts have momentum that is second to none in the postseason.
Rivers does utilize running backs LaDainian Tomlinson and Darren Sproles as receivers, but he is far from a dink-and-dunk passer. The mindset of the Chargers offense is as follows: Why go short when there's a deep route to hit on practically any given play?
"I think it's going to be key for our guys is to get depth in our drops, because they don't like short passing," Colts linebacker Gary Brackett said. "(Rivers) throws the intermediate route, but he likes to throw the ball downfield to those receivers. And he has very capable receivers in (Vincent) Jackson and (Chris) Chambers, who make a ton of big plays for him."
The Chargers' defense finished the season 25th overall in the NFL and next-to-last against the pass. Those aren't exactly the type of credentials that provide encouragement against a team like the Colts, who have the league's fifth-ranked passing game, or a quarterback like Manning, who ranks sixth in the NFL in passing yards (4,002) and fifth in touchdown passes (27).
After reaching the bye week at 3-5 following a 37-32 loss to New Orleans in London, Chargers coach Norv Turner felt it was time for a change on defense. He fired defensive coordinator Ted Cottrell and replaced him with Ron Rivera, who formerly coached the Chargers' inside linebackers.
In the eight games since, the Chargers have allowed about one fewer touchdown per game, thanks in large part to a more aggressive mentality that Rivera has instilled in the defense.
"They're attacking," Rivera said. "That's kind of what we tried to do, too -- get them back into the attacking mode."
Rivera's other challenge was to get the Chargers defenders to do a better job of coping with the absence of the team's best defensive player -- outside linebacker Shawne Merriman -- out for the entire season with a knee injury. Among the first points the coach stressed to the unit after being promoted was that one player's absence shouldn't take down an entire defense.
"I said to the guys, 'You mean to tell me that 11 guys came back together (from a strong 2007 season), we lose one guy at the beginning of the year and 10 guys can't pick it up? You guys have to learn to rally around each other,'" Rivera recalled. "And they have. The players have really done a great job in understanding how things have to be done and we have to continue that, continue to grow, and get better as a unit."
Of course, they must be careful about blitzing Manning, because he is the NFL's best at reading the blitz and reacting quickly. His receivers also do an exceptional job of adjusting their routes accordingly. If a blitzer doesn't get to Manning before he gets rid of the ball, there's a good chance the Colts will end up with a big play.
Rivera no doubt had that in mind when his defense faced Manning on Nov. 23 in San Diego. The Colts won, 23-20, snapping a three-game losing streak to the Chargers that included a divisional-round playoff game last year at Indianapolis. Manning threw two touchdown passes and had one interception. But the Chargers only managed to sack him once.
"It's all about the opportunities and the situations," Rivera said of blitzing Manning. "You just don't do it to do it against him. And the other thing is you've got to be able to handle his adjustments and be ready to cope with that. When you do it, you've got to attack the way they are trying to attack you as opposed to just going and doing it.
"As we study these guys, there are some opportunities that we feel we can get some pressure and there are other opportunities where we have to make sure we're in good coverage position. You have to make sure you're good at your (coverage) disguises, good at (knowing) your landmarks and make sure that your spacing is as good as theirs."
The Colts' defense has overcome its share of hardships. Safety Bob Sanders missed nine games because of injuries. Brackett has been out for the last four games with a broken fibula.
But the unit has persevered and wound up finishing the regular season ranked 11th overall. The Colts are sixth in the NFL against the pass and have given up a mere six touchdowns through the air, which is a league record for a 16-game season. Those numbers will be put to a severe test by Rivers, who tied the Saints' Drew Brees for the NFL lead with 34 touchdown passes, including two against Indianapolis. In last year's divisional playoffs, Rivers threw for 264 yards and three touchdowns against the Colts. As Colts coach Tony Dungy put it, "He carved us up last year."
The Colts should be able to generate a fair amount of pressure with a defensive line that features two of the NFL's best pass-rushing ends in Robert Mathis and Dwight Freeney, both of whom were selected to the Pro Bowl. Mathis finished the year with 11.5 sacks, while Freeney had 10.5.
The Colts are fourth in the AFC in giveaway/takeaway ratio at plus-9, and seventh in takeaways with 26 (15 interceptions and 11 fumbles).
"Our main thing is creating turnovers, creating havoc," said Brackett, who won't play against the Chargers. "Sometimes we stay on the field a little bit longer than we would like. Our third-down conversion rate (47.4 percent) is not where want it. But I think guys really step up in the red zone and make plays when they have to."
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