I wanted to find some way to explain just how good LSU's new-look defense has been this season. I was a bit down on the Tigers prior to the season because they lost the best player from each level in Drake Nevis, Kelvin Sheppard, and Patrick Peterson. Obviously, that pessimism was unwarranted.
The first place I looked was to rushing defense. I remember seeing somewhere a while ago that LSU's rushing yards allowed per game had been rising every year since the 2007 national championship season. That is correct: LSU allowed 106.10 yards per game in '07, 110.15 in '08, 133.38 in '09, and 137.31 in '10. I hate the NCAA rushing stats though, as they count sacks as runs. Besides, yards per carry is better than yards per game.
So I looked into rushing yards with sacks removed, and I was blown away. I then threw in the passing defense, and the picture gets even uglier for LSU's opponents:
| Season | Carries | Yards | YPC | Comp/Att | Pct. | Yards | Yds/Att | TD | INT | Pass Eff. |
| 2007 | 427 | 1767 | 4.14 | 212/451 | 47.0% | 2558 | 5.67 | 19 | 23 | 98.35 |
| 2008 | 393 | 1604 | 4.08 | 227/425 | 53.4% | 2800 | 6.59 | 15 | 8 | 116.64 |
| 2009 | 473 | 1879 | 3.97 | 222/416 | 53.4% | 2525 | 6.07 | 13 | 13 | 108.41 |
| 2010 | 444 | 2050 | 4.62 | 196/344 | 57.0% | 2208 | 6.42 | 15 | 19 | 114.24 |
| 2011 | 169 | 484 | 2.86 | 117/214 | 54.7% | 1109 | 5.18 | 5 | 8 | 98.44 |
In terms of yards per carry, LSU's defense was marginally better than 2007 in the following two years, though it got noticeably worse last year. This year? Ho-lee crap. LSU is holding opponents under three yards per carry so far. Keep in mind that one of those opponents was Oregon, the nation's current leader in YPC at 7.37 (two sacks included, so it's actually marginally higher). The Ducks officially managed just 3.4 YPC against LSU, and there wasn't even a sack to help that number. Think about how much higher Oregon's season figure would be had it not faced LSU.
So as it turns out, pass defense and not rush defense was the real area where the subsequent years weren't up to the 2007 standard. Opponents' yards per pass, completion percentage, and passing efficiency were all up in 2008-10 over '07. Passing TDs were down, yes, but INTs weren't as high.
This year's completion percentage is also higher than 2007's impossibly low figure, but the yards per attempt is actually half a yard lower. Those competing factors even each other out essentially in producing the passing efficiency figures that are basically the same. Keep in mind that LSU also has faced West Virginia, one of the nation's most prolific passing teams. Geno Smith is 29th in passing efficiency at 152.38 despite his 122.3 against the Tigers.
So far, LSU is sporting a rough equivalent to its best recent passing defense along with by far its best rushing defense. We'll see what Arkansas and Alabama do to those numbers, but LSU will probably sustain its pace this weekend with Tyler Bray out for Tennessee. John Chavis has everything put together just right in Baton Rouge this season.