And weâ€re back! Sooner than expected but DMQ is a harsh task master. Actually, NCAA 2012 was released Tuesday and once I get my hands on it, there goes any productivity in my life. Youâ€re lucky you are even getting this post. However, since Amazon hates me for unknown reasons resulting in my copyâ€s delivery being delayed until today, here you go.

On to the defense! And even more charts. (Charts, if I may say so myself, that are far nicer looking than anything produced on that hack website SubwayDomer.com)

For those who are too lazy to scroll down a couple of posts, we are looking at how the 2010 Irish stack up against the BCS Top 10 from 2005 through 2010 in a variety of stats and what phases of the game ND would have to improve to make a BCS appearance after the 2011 season. (Spoiler! Most of them)

Part 2 – Defense

That graph is much better looking than anything produced for the offensive stats. The 2010 Notre Dame Defense was pretty damn good. We were above the BCS average in 4 of the 5 S&P+ categories. Our overall Pass D was fantastic. Our Rush D, while not as “dominant” as our passing defense, was still above the BCS average. However, as the dents in my remote and the holes in many of your walls can attest, our Passing Down D was the weakest part of our defense last year. Anecdotally, I feel like this was a weakness earlier in the year, and our Dâ€s stellar performance over the last 5 games was mainly due to them improving on getting off the field on 3rd down. If you remember from the post about Offense, Passing Down performance was the biggest weakness. Not really sure if that means anything besides that ND must improve on both sides of the ball (and that watching ND on 3rd down probably took years off my life) but it did interest me.

As you can see below, the tradition stat of 3rd down conversion performance confirms that ND definitely has to improve getting off the field on 3rd down.

For those curious about the outliers, 2009 Alabama, 2009 Texas, 2007 USC, & 2009 Iowa (!) put up some of the better numbers. 2007 Hawaii, and 2009 Georgia Tech managed to account for the worst D performances.

Next, weâ€ll look at how efficient our defense was. DFEI  (as a reminder) is the opponent adjusted. ND performed well under the DFEI measure but unlike S&P+, ND was below efficient. As FEI is drive-based more so than play-based, this makes sense given the less-than-stellar performance on passing/3rd down. Also, the way DFEI is measured, the more negative your DFEI, the better/more efficient your defense was. While not a poor comparatively to the BCS average as the offense was, the Defense does need to improve itâ€s efficiency in 2011. The 2009 Georgia Tech shows up again with that abymsal +.23 DFEI. That defense was just awful but hey, they played in the ACC, had an amazing offense, and well, Paul Johnson.
On FootballOutsiders, DFEI was broken out in to 4 sub categories. This was done for first time for the 2010 so while we canâ€t compare ND against the BCS average, we can dig deeper into NDâ€s performance.

• FD: First Down rate, the percentage of opponent offensive drives that result in at least one first down or touchdown.
• AY: Available Yards, yards earned by the opponent’s offense divided by the total number of yards available based on starting field position.
• Ex: Explosive Drives, the percentage of each opponent offense’s drives that average at least 10 yards per play.
• Me: Methodical Drives, the percentage of each opponent offense’s drives that run 10 or more plays.

ND managed to be ranked 11th in the first 3 categories and 71st in Me. The 71st in Me is somewhat expected given Diacoâ€s Bend but donâ€t Break philosophy. However, that coupled with the 11th in FD was a slightly unexpected result at first glance. Essentially, ND was fairly impressive in forcing 3 and outs (about 40% of the time). Then, on the 60% of the drives that were not a 3 and out, ND gave up a Methodical drive around 25% of the time. Stat Nerd Tangent Over!

Time for graphs stats (or as I like to call it, why opponent adjustments are crucial context)
Letâ€s start with yards per play. Remember, in this section, less is more.

In all 3 measures, and unlike most of the Football Outsider stats, ND was somewhat worse than the BCS average. Opponent adjustments or not, all of us fans would like for these numbers to be more in line with the rest of the BCS teams. Someone with far more time than I could probably break these out pre and post Tulsa so see if the dismal performances against Navy, Skunkbears and Stanford elevated these numbers. While the defense was better than one might remember, it definitely wasnâ€t a BCS caliber defense for those first 7 games.

And if we bring yards per game, the results arenâ€t any better looking.

In looking at both Yards per Game and Yards Per Play, the rush D was farther behind where weâ€d like it to be compared to the Pass D. Giving up 500 yards to Denard Robinson (did you know he doesnâ€t tie his shoelaces?) and ~1,000 yards to Navyâ€s Heisman trophy winning fullback wonâ€t help any counting stats. If we bring back Rush D S&P+, we can see that we are just barely above average. Since Denard and Navy ran all over most teams they faced, our performances, while pathetic, were at least mirrored by other defenses in CFB.  In the end, we need our rush D to continue itâ€s performance over the last 5 games if we want to see a BCS game after the 2011 season.

Notre Dameâ€s defense took a giant leap forward near the end of the season. The last 4 games were some of the most fun some of us had watching games in a long time. If the Irish D can keep up that performance, we could be in for a special year on defense. As Bill C of Football Study Hall/Football Outsiders noted in his 100X more awesome preview (link), we were possibly the top defense in the country over those last 4 games.

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