Anatomy of a Collapse

Going into week 9 of the 2008 season, the Washington Redskins were 6-2. Their two losses came in a low scoring affair against the Giants at the Meadowlands, and in a fluky 19-17 game hosting the Rams. They had beaten division rivals and pre-season darlings Dallas and Philadelphia, both on the road. They outscored the prolific Saints and Cardinals offenses. The playoffs were a virtual certainty, and challenging the Giants for NFC supremacy wasn't out of the question.

Then, the Redskins dropped the next 5 out 6 games, falling to 7-7 and eliminating themselves from playoff contention in all but the most improbable scenarios. In fact, despite a late-season win over the Eagles this week, they have been officially eliminated. What went wrong?

Before I go any further, keep in mind that maybe nothing went wrong. Say the Redskins had about a 50/50 shot at winning every one of their games--essentially a coin flip. It's not terribly uncommon for 8 coin flips to turn up 6 heads and 2 tails. And it wouldn't be unfathomable that another few flips wouldn't result in 5 tails and a head or two. In fact, it's looking like the Redskins will finish either 8-8 or 9-7, essentially a coin flip of a team. There's nothing that says a team's 8 wins have to be evenly paced throughout a season.

But teams aren't coins, so I'll take a deeper look at the Redskins' performance game by game. I'll look at their four major components--running and passing, on both offense and defense.

I measure passing performance by adjusted net yards per attempt. This is passing yards minus sack yards, minus 40 yards per interception, per drop back. Running performance is measured simply by yards per run.

Opponent strength is an important factor. For each game I adjust the Redskins' performance in each phase of the game according to how strong the opposing team is in the opposite phase. I simply added the opponent's difference from average to the Redskins' efficiencies. For example, if the Redskins' offensive passing efficiency was 5.0 yds per attempt, and their opponent's season-long yds per att allowed was 1.5 yards above league average, I gave the Redskins 6.5 yds per attempt.

The graphs below plot performance as a 4-game moving average. This is to account for the natural game-to-game variation in performance. We shouldn't expect a team to maintain steady efficiencies in every game they play. Ultimately, the moving average allows us to see team-wide season-long improvements or declines while accounting for opponent strength.

The first graph illustrates opponent-adjusted offensive efficiency for passing and running, and the second illustrates defensive efficiencies.





We can see that the defense was relatively steady all year. Oddly, it looks like the pass defense improved following the eighth game, which is when the 1-5 slide started. (Remember lower is better for defense.) The run defense was rock-steady all year.

The rushing offense was equally steady and remained above-average all year. But Washington's passing game showed a steady decline throughout the season.

So it was the passing game, not Portis, not the secondary, not the pass rush. My theory is that they threw too few interceptions early in the year. That's not a typo. I think head coach Jim Zorn or quarterback Jason Campbell became captive to the idea that they were winning because they weren't throwing interceptions. While a lack of turnovers certainly helps win games, if it becomes a passer's primary goal it could be harmful.

Interceptions are a part of the bargain, a natural consequence to throwing the ball. You can guarantee zero interceptions by playing in an extremely conservative way, tossing short passes, taking sacks, or throwing the ball away anytime a defender is in the same zip code as the receiver. You can minimize interceptions, but you'll lose every game doing it.

At some point in the risk-reward continuum, there is an optimum level of risk in passing strategy. I'm guessing the Redskins found themselves too far on the conservative side of optimum.