How McDermott's pass defense stacked up

With Sean McDermott out, I wanted to take a look at just how much the Eagles' defense dropped off in the past two years with him running the show.

We'll start with the pass defense, then move on to the run and finish with some overall numbers.

If you missed my thoughts from Saturday night on the McDermott firing, click here.

What I did here was measure how the Birds' D stacked up statistically in a number of categories for two different time periods. One was 2009-2010, with McDermott at the helm. And the other was from 2004-2008, the last five years of the Jim Johnson era.

I looked at both the actual numbers and also league rank - which is in parentheses. Certain numbers can be up league-wide in any given year so league rank gives a good indication of how the Eagles stacked up against their competition.

Here's a chart with the comparison of how the pass defenses measured up:

Let's tackle these one-by-one:

Yards per game: Count me among the many who don't believe this is a great measure of defensive success, but since it's such a widely-used stat, it's at least worth mentioning. Under McDermott, the Eagles allowed 216.6 passing yards per game for an average league rank of 15th. In the previous five years, they allowed 199.6. The Birds were obviously better in this category from 2004-08, but the discrepancy is not huge when you look at where they ranked against their peers.

Yards per attempt: This is a better number because it measures how effective opponents were when they passed against the Eagles. As you can see, the numbers are pretty similar, but again, the Eagles were slightly better from '04-'08.

Passing touchdowns: This is the huge one. We all know about the Eagles' historically bad red-zone defense in 2010, and the numbers here reflect that. In two years under McDermott, opponents had a total of 58 passing touchdowns - 31 in 2010 and 27 in 2009. From '04-'08, opponents averaged only 18.4 passing touchdowns per season against the Eagles. The Birds surrendered 19 touchdown passes or fewer in four of the five previous seasons before McDermott.

Interceptions: The Eagles were actually significantly better here under McDermott. Then again, Asante Samuel didn't join the team until 2008, Johnson's last season. The Eagles finished fourth and third in interceptions in 2009 and 2010. They failed to finish in the top five in interceptions the previous five seasons.

Sacks: The numbers here are similar. And they might be more of a reflection of the system than anything else. The Eagles have finished in the top 10 in sacks in six of the last seven seasons. They've finished in the top five three times.

Passes of 20+ yards: The Eagles were worse here under McDermott. They gave up 54 pass plays of 20 yards or more in 2010, 24th in the league. Then again, 2010 was the first season without Sheldon Brown. The Eagles played with Ellis Hobbs and Dimitri Patterson at right cornerback. McDermott was also not given the luxury of having an all-time great in Brian Dawkins at free safety.

Opponents' QB rating: This one was almost identical, which surprised me. The Eagles finished 11th in this category both seasons under McDermott. Their average finish the previous five seasons was 10.4.

Overall, what do the numbers say? The Eagles could not keep opponents out of the end zone the last two years, even if many of the other numbers were similar. They created more turnovers against the pass, but also gave up more big plays.

I do think it's important to rewrite history. Johnson was a great defensive coordinator - an all-timer. But even his units struggled at times. In 2007, the Eagles allowed 215.6 passing yards per game, almost the exact amount they allowed under McDermott. In 2005, opponents averaged 7.0 yards per attempt and threw for 24 touchdowns against the Eagles.

The Bird had only 11 interceptions in 2007 and allowed 47 completions of 20 yards or more in 2008.

The Eagles' pass defense was a weakness under McDermott, and he needs to bear some responsibility for that, but by most statistical measures, it was not an elite unit in the five previous seasons.

The next breakdown will look at the run defense.

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