Game Preview: Kansas City Chiefs at San Diego Chargers, Chargers on Defense

The San Diego Chargers defense really couldn't ask for a better start to the season in terms of matchups.

In Week 1, they got to face a should-be-retired Donovan McNabb and a not-quite-healthy-yet Visanthe Shiancoe. The end result was McNabb completing less than 50% of his passes for 39 total passing yards, completing just 1 pass for 2 yards in the second half of that game.

In Week 2, with their confidence high, the Bolts and Greg Manusky got a measuring stick to see how good or bad the passing defense really was. Final verdict? There are still some holes to fill, which Tom Brady stated loudly to the tune of 423 passing yards, 3 passing TDs and a completion percentage of 77.5%. With an hour's worth of tape to look at to try and right the ship, the Chargers get to head back to the minor leagues in terms of opposing QBs.

For those unfamiliar with the QB Rating stat, it's somewhat flawed. However, what it is a good metric of is if a QB is able to consistently make plays through the air without making mistakes.

JaMarcus Russell is the poster-child of bad QBs of late, and in his last season he completed less than 50% of his passes (for a 5.2 yards per attempt average) and threw 3 TDs against 11 Interceptions. That equaled out to a QB rating of 50 even. If we view Tom Brady as the poster-child of good QBs, at least in terms of making plays without making mistakes, and look at his 2010 MVP campaign.....he completed over 65% of his passes and finished with 36 passing TDs and a 7.9 yards per attempt against just 4 Interceptions. He finished with a QB rating of 111 even. Got it?

The worst 3 QBs in the NFL, that have started games thus far, in terms of QB rating are as follows: Luke McCown (30.6), Matt Cassel (50.4) and Donovan McNabb (71.3). So, as bad as McNabb was against the Chargers (which amounts to half of his season thusfar), he is still having a better year than Matt Cassel. Matt Cassel is only having a better season than McCown, who was just benched for a rookie QB. There could be some potential here.

So why the drop-off in performance from the Chiefs from 2010 to 2011? Well, lots of reasons. Number one, Cassel is now playing without his starting TE (Tony Moeaki) and star RB (Jamaal Charles). Number two, Charlie Weis (who was largely credited with the turnaround of the Chiefs offense last season) is now busy calling plays for the Florida Gators and has been replaced by some mixture of Todd Haley and Bill Muir that isn't working. Number three, even last season this was an offense that was meant more for not making mistakes than for coming from behind. Now, with their defense struggling mightily, they're often being asked to do just that.

It's not too risky to assume that Matt Cassel will have similar results against the Chargers that Donovan McNabb had, but then again.....this is a team that used to be the best in the league at making JaMarcus Russell look like a decent QB. There could be issues.

Here's the numbers. The San Diego Chargers defense is.....

• 17th in the league for yards allowed per game.
• 26th in the league for yards allow per play.
• 22nd in the league for points allowed per game.
• 30th in the league for 3rd down conversion percentage against.
• 28th in the league in terms of penalties against.
• 19th in the league in terms of sacks with 4.0.
• 19th in the league in terms of interceptions with 1.
• last in the league in terms of forced fumbles with 0.