Each week, John Gennaro gives fans of the San Diego Chargers three reasons to be pessimistic about the team's chances in their upcoming game. This week, we look ahead to their matchup with the Buffalo Bills.

We're Wrong About the Defense

You know how San Diego Chargers fans are riding high, talking about how the defense looks greatly improved from last season? I know, I'm one of them. Check out this stat I just invented:

On drives that start on the 23 yard line or better, Chargers opponents have scored on six of seven drives.

On drives that start on the 22 yard line or worse, Chargers opponents have scored on one of twelve drives.

Small sample size, I know, but so far you can pretty much predict whether or not the opposing team will score on the 2014 San Diego Chargers based on where their drive begins. To me, that doesn't say dominating defense.

Give any NFL offense a lot of chances at a long drive and some mistakes will be made along the way. Dropped passes, penalties, missed blocks....these types of things. The consistency required is the most difficult part about scoring on a long drive. The Chargers defense, which has done an average job of not giving up big plays down the field, are benefiting from a spectacular special teams unit.

That being said, I'm now less confident that the Chargers can stop the powerful Bills running attack or their efficient passing offense. This game will be won by special teams and intangibles, which puts it squarely in favor of the home team. Not only did they not have to travel anywhere this week, but they did not play in 120 degree heat last week and didn't have to brawl with the Super Bowl champs.

No Melvin Ingram

To make matters worse, the guy that I called the MVP of San Diego's win over the Seattle Seahawks will not be around for their game against the Bills. He's out with a hamstring injury.

The difference between last year's defense and this year's defense is quite simple. The pass rush on 3rd-and-long actually exists now, and it didn't last year. You can attribute that to Dwight Freeney, Melvin Ingram, Jerry Attaochu, or possibly even John Pagano. However, take one of those pieces away and it takes a pretty dramatic step back.

The plan for Dwight Freeney this season was for him to be a 3rd down specialist, coming in on passing downs to simply go after the QB. This will be the second week in a row where he will be asked to be the starter, and will either be challenged in coverage or will force Pagano to change much of his base defense as a result of Ingram's injury. I thought Seattle made a big mistake by not testing him much.

The Chargers will need to keep their defense off the field and win the special teams battle if they hope to pull out a victory, because they will likely struggle to slow down the Buffalo offense.

No Ryan Mathews

I don't love to simplify things down to this level, but here's a really simple way to look at the Miami Dolphins' season so far:

Week 1: Knowshon Moreno runs wild on the Patriots, leading to a 33-20 victory.

Week 2: The Bills knock Moreno out of the game on his first carry (for 4 yards), and beat the Dolphins 29-10.

This may not be the best defense in the league, but they're loaded with talent. If they can take your biggest weapon out of the game and point their focus straight at one half of your offense, they are lethal. They sacked Dolphins QB Ryan Tannehill four times in that game and had him running on almost every drop-back, all while getting good coverage on receivers down the field. This was mostly because they did not fear the running game after Moreno's departure.

Mathews would have been the key to this game, had he been healthy. The Chargers would have had him carry the ball 20+ times right at the pass-rushers that the Bills have on their defensive line, and that would have kept the chains moving and the defense honest. I'm convinced that this would have been the game plan and execution.

Without Mathews, things get tricky. Donald Brown, who will likely take over Mathews' spot as San Diego's #1 RB, last got 20+ carries in January 2009 against Buffalo. That is, the Buffalo Bulls. Donald Brown was still a Husky, playing for UConn, taking on the Bulls in Toronto's International Bowl.

Brown has never really been trusted as a #1 RB or as a workhorse, which means the Chargers coaching staff might allocate some carries for undrafted rookie RB Branden Oliver (a former Buffalo Bull), who played great in the team's first 2014 preseason game before disappearing and fumbling kickoffs due to loud road crowds. That may not be who you want leading your offense for a road game in a loud stadium.

Say what you want about Philip Rivers, but the coaching staff knows that the offense works best when he throws it about 30 times. When he inches up towards 40, it's a sign that the team is in danger of losing the game. San Diego would like for him to not have to throw it as much as he has the first two weeks of the season, but the loss of their starting RB makes that more difficult.

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