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19 Jun 2009

Varsity Numbers Gets Defensive

by Bill Connelly

In the last couple of VN columns, we've been taking a walk back through 2008 stats. The jaunt wraps up today with a look at the top defensive rankings in the country.

TCU was No. 1 in Total Defense last year, but they played in the Mountain West -- a mid-major level conference -- so the obvious question is whether their (perceived) poor strength of schedule hurt their S&P+ rank. It didn't. Their non-conference slate included top offenses Oklahoma (second, Close-Game Offensive S&P+) and Stanford (12th), and the Mountain West contained strong offenses as well, including BYU (sixth) and Utah (22nd). They held Stanford to 14 points, BYU to seven, and Utah to 13, and held Oklahoma to its lowest regular-season total (35 points). They were positively dominant in 2008, and despite playing in a non-BCS conference, they had by far the best defensive "+" numbers.

The only major category in which TCU wasn't the class of the country was Passing Downs, where opponents had no chance against USC. Meanwhile, teams like Iowa and Connecticut were competent during Standard Downs and devastating on Passing Downs. It was Iowa's Passing Down strengths that led to their upset of Penn State.

2008 Defensive "+" Rankings
Rank Team Defense S&P+ Rushing Passing Standard Downs Passing Downs
1 TCU 170.3 166.0 (1) 176.4 (1) 159.6 (1) 144.8 (6)
2 Texas 146.4 147.1 (2) 149.0 (3) 130.6 (3) 145.0 (4)
3 USC 141.7 133.5 (6) 147.9 (4) 137.5 (2) 172.2 (1)
4 Florida 135.1 124.0 (15) 146.3 (5) 126.2 (5) 122.3 (19)
5 Boise State 133.0 132.1 (7) 128.1 (9) 125.1 (7) 134.1 (10)
6 Ohio State 132.3 114.4 (32) 150.0 (2) 123.6 (10) 144.8 (5)
7 Oklahoma 129.3 129.8 (9) 129.3 (7) 124.8 (8) 139.6 (9)
8 Alabama 123.5 139.6 (5) 113.6 (25) 126.8 (4) 123.8 (16)
9 Central Florida 123.1 125.7 (12) 120.4 (10) 119.4 (13) 122.5 (17)
10 Tennessee 122.8 146.0 (3) 103.8 (49) 125.7 (6) 118.1 (26)
11 Iowa 122.2 140.5 (4) 110.5 (30) 113.5 (24) 149.9 (2)
12 Wake Forest 120.9 122.2 (17) 120.2 (11) 116.5 (18) 112.0 (38)
13 Connecticut 120.7 113.0 (33) 128.3 (8) 112.7 (25) 146.0 (3)
14 Cincinnati 120.7 122.3 (16) 117.9 (14) 115.8 (20) 119.9 (22)
15 Penn State 120.5 130.3 (8) 111.4 (29) 118.5 (15) 131.7 (12)

Central Florida (43rd in Total Defense and 54th in Scoring Defense, but 9th in Close-Game S&P+) makes an interesting appearance on the list. There is no single explanation for their S&P+ strength. They did play solid offenses like Tulsa and South Florida, but nothing special. What probably helps their defensive numbers here is that their offense was so terrible (120th out of 120 in Close-Game Offensive S&P+) that opponents likely got a lot of short fields to work with, which clearly wasn't the UCF defense's fault. Plus, in blowout losses to UTEP (58-13) and Tulsa (49-19), the game got out of hand so quickly that the "Close-Game" limitations doesn't completely penalize them.

One should also note the high presence of Oklahoma (7th) in these rankings. The Sooners caught a lot of flack in 2008 for some defensive struggles, but A) they played just about the best series of offenses of anybody in the country, and B) their struggles mainly came when they were attempting to replace injured middle linebacker Ryan Reynolds mid-season. They got the kinks worked out toward the end of the season, holding Texas Tech, Missouri, and Florida all well below their season averages.

Success Rates

Top Defenses in Success Rates+
Rank Team SR+
1 TCU 163.09
2 Texas 130.68
3 Oklahoma 126.67
4 Boise State 121.07
5 Central Florida 119.84
6 USC 119.04
7 Michigan 118.50
8 Virginia Tech 118.24
9 Oregon State 117.20
10 Florida 117.05

The most interesting name on this list is Michigan. They were seventh in Success Rates+ but 62nd in PPP+. That suggests that they played pretty efficient defense overall, not giving up consistent gains, but the breakdowns they did suffer were large ones, and they gave up far too many big plays.

Points Per Play (PPP)

Top Defenses in PPP+
Rank Team PPP+
1 USC 181.93
2 TCU 179.63
3 Texas 167.74
4 Florida 163.74
5 Ohio State 158.37
6 Boise State 151.39
7 Penn State 138.66
8 Alabama 137.81
9 Tennessee 136.41
10 Iowa 136.09

USC was good in efficiency -- they were sixth in Success Rates+, but they were beyond outstanding in terms of avoiding the big play. When teams scored on them, it was likely because of short to medium gains and sustained drives. They just did not allow many big plays last year.


Top Defensive Rushing S&P+
Rank Team S&P+
1 TCU 165.95
2 Texas 147.06
3 Tennessee 145.97
4 Iowa 140.48
5 Alabama 139.58
6 USC 133.48
7 Boise State 132.13
8 Penn State 130.33
9 Oklahoma 129.78
10 South Florida 127.86

Need proof of the quality of TCU's defense? Here it is: Oklahoma's Chris Brown and DeMarco Murray made one of the best running back duos in the country. Brown was extremely efficient, while Murray became more explosive as the year progressed and he became further removed from his 2007 injuries (before suffering another injury against Missouri in the Big 12 Championship, anyway). Against TCU, they combined for just 50 yards on 26 carries.

Meanwhile, notice Tennessee's presence on the list. Thanks to All-World DB Eric Berry, you would expect the Vols to have maybe showed up in the Top 10 for pass defense, but they did not (they were 49th). They did, however, possess a pretty stout run defense that, if their offense had not been so awful (80th in Close-Game S&P+, 48th Rushing S&P+, 100th Passing S&P+), would have kept them in games and potentially won enough to save Phil Fulmer's job.


Top Defensive Passing S&P+
Rank Team S&P+
1 TCU 176.44
2 Ohio State 150.01
3 Texas 148.95
4 USC 147.88
5 Florida 146.26
6 San Jose State 133.36
7 Oklahoma 129.27
8 Connecticut 128.26
9 Boise State 128.09
10 Central Florida 120.42

San Jose State was another team with a solid defense and atrocious offense (117th in Close S&P+). They held opponents to 5.7 Yards Per Pass and a 9-16 TD-INT ratio, and the competition was good enough to get them to 6th in Passing S&P+ as well.


As with the Offensive Buffet column, the goal here is to look at teams who had a little too much success on Passing Downs as compared to Standard Downs. Is there a connection between disproportionate success here and a rise or fall the next year?

Teams With Disproportionately High PD S&P+, 2008
Rank Team PD S&P+ SD S&P+ Ratio Overall S&P+ Rank
1 Texas Tech 142.26 98.71 1.44 45
2 Iowa 149.89 113.49 1.32 11
3 Connecticut 146.04 112.67 1.30 13
4 Pittsburgh 140.93 110.11 1.28 16
5 USC 172.24 137.52 1.25 3
6 Tulane 110.04 88.78 1.24 89
7 Temple 121.11 98.57 1.23 54
8 San Jose State 129.89 106.71 1.22 28
9 South Carolina 133.16 110.71 1.20 24
10 Louisiana-Lafayette 102.62 85.38 1.20 100
11 UCLA 129.29 107.71 1.20 37
12 Northwestern 120.37 100.80 1.19 43
13 Miami (OH) 93.03 78.08 1.19 113
14 Army 113.41 95.51 1.19 59
15 Ohio State 144.79 123.63 1.17 6

Some great defenses in there, along with some terrible ones. Now let's look at teams with the most disproportional 2007 performance and how their disproportionality translated to 2008 success.

Teams With Disproportionately High PD S&P+, 2007
Rank Team Ratio Change*
1 Troy 1.44 +7.88%
2 Michigan 1.33 -11.13%
3 Vanderbilt 1.27 -3.01%
4 Hawaii 1.27 -0.27%
5 Stanford 1.25 -9.19%
6 Ohio State 1.22 -8.06%
7 Georgia 1.20 -12.39%
8 Wisconsin 1.19 -13.46%
9 UCLA 1.19 -16.10%
10 Pittsburgh 1.19 +3.61%
11 UNLV 1.18 -9.29%
12 Texas A&M 1.18 -17.38%
* This represents the change in overall Close-Game S&P+ from 2007 to 2008.

In all, ten of 12 teams with a disproportionality ratio of at least 1.18 saw a fall in Defensive S&P+ from 2007 to 2008, and eight fell at least 8 percent. Clearly experience and overall quality play a role here -- there is not much concern for Miami (OH)'s defense regressing considering they were 113th in 2008 -- but disproportionality alone seems to be a decent warning sign for a fall. With a depleted pass rush and by far the highest disproportionality, Texas Tech should see a decent-sized fall from their spot as the 45th overall defense. They didn't have an amazing defense in 2008, but they made big plays, especially on Passing Downs, and that allowed them to utilize their experienced offense and go 11-1. With less experience on offense and a regression on defense, they should fall back to the 7-5 or 8-4 range in 2009.

The next team on the list, Iowa, has had a reputation for always having solid defenses under Kirk Ferentz, but until 2008 they had not finished in the Top 15 in Total Defense since 2004, so this surge back to near the top of the rankings will probably come with at least a slight fall in 2009. Meanwhile, both Connecticut and Pittsburgh have had decent defenses in the past, but they will probably regress a bit as well; Connecticut especially should fear at least a slight fall, especially with the loss of second-round draft picks Darius Butler (cornerback) and Cody Brown (linebacker).


So the big questions resulting from this rundown of stats have to be, 1) Was TCU's defense really better than USC's? and 2) Can the Horned Frogs duplicate this magnificent defensive effort in 2009? The answer to 1) is clearly debatable -- if one is against the thought of TCU being better than its top BCS-level counterparts (USC, Texas, Florida, etc.), then there will be no changed minds once numbers are brought into play. That said, they were so dominant, against a rather respectable bunch of offenses, and statistically, they were so much better than anybody else (their S&P+ was 24 points higher than that of second-ranked Texas), that they have a definitive case for having been the best defense.

The answer to 2), however, is "probably not." To be sure, Gary Patterson's defense will still be strong, but with the loss of seven starters, including three linebackers (Jason Phillips, Robert Henson, Stephen Hodge) taken in the 2009 Draft, they will likely take a step back into the 10th to 25th range in terms of overall S&P+.

In all, most of the top defenses from 2008 face heavy turnover in 2009. Second-ranked Texas has to rebuild its defensive line after losing Brian Orakpo, Roy Miller, and Henry Melton; third-ranked USC had eight defensive players drafted in April. Meanwhile, fifth-ranked Boise State only lost one starter to the draft but has to replace six starters overall. Only fourth-ranked Florida, and its ridiculous 11 returning starters, looks to hit the ground in 2009 playing better than it did in 2008.

Posted by: Bill Connelly on 19 Jun 2009

9 comments, Last at 22 Jun 2009, 9:02am by Theo


by lionsbob :: Fri, 06/19/2009 - 5:42pm

I think Alabama can be better on defense next season as well. They lost 2 starters, but Greenwood was more of a role player-losing Rashad Johnson is huge though. But the talent is there to be even better and they probably have one of the best front 7's in college football (and a darn good secondary).

by Kibbles :: Fri, 06/19/2009 - 5:54pm

Florida didn't just return all 11 starters, it returned all 11 top backups, too. That's right, the entire TWO-DEEP returns intact from last year's 4th-ranked unit.

by Pete (not verified) :: Mon, 06/22/2009 - 7:30am

I believe one of the backup DT's transferred out of Florida (he started late in the season or in the SEC championship, but I forget his name). Could Florida lose a couple game of some its players (Jenkins of the taser) due to legal issues?

by Theo :: Mon, 06/22/2009 - 9:02am

Torrey Davis perhaps.

by lionsbob :: Sat, 06/20/2009 - 5:34pm

Does Florida play anyone with an actual offense this season? Maybe LSU and Georgia?

by Kibbles :: Sat, 06/20/2009 - 11:24pm

LSU and Georgia are both big maybes. LSU's never really had any big-time offenses, and every Georgia offensive player is a question mark except for A.J. Green and the offensive line. I also wouldn't be surprised if Kentucky wound up with a good offense, because I have a lot of respect for what Joker Phillips has managed to do out there. Other than that, I don't think Florida has any chance of facing a top-10 offense before the SEC Championship Game (Alabama will probably be good on offense, and Ole Miss will probably be extremely good). I have a feeling we're going to see some incredible numbers from Gainesville this year.

by Bill Connelly :: Sun, 06/21/2009 - 11:12am

The back-to-back trips to Lexington and Baton Rouge definitely offer the biggest upset potential, I would think. Nobody's going to beat Florida because they were better on offense and defense--just that it was a tricky game and a one-of-those-weeks situation.

by R (not verified) :: Sun, 06/21/2009 - 2:31pm

The question isn't whether TCU's defense was better than USC's. USC had the third ranked defense. Texas was #2, which received almost no mention in this article. USC's defense wasn't better than that of Texas, and neither was TCU's.

by Kibbles :: Sun, 06/21/2009 - 10:44pm

Wait, Texas is better than USC because they looked better in these numbers... but TCU isn't better than Texas despite looking better in these numbers? You can't use a rating system when it supports your point and then discard it the second it disagrees with said point.

The question is USC vs. TCU because popular opinion is that either USC or TCU was the best defense in the country. If you're going to bring up Texas and ignore the S&P+ numbers, I'd argue that Florida was better than Texas based against results against common opponents.