Before Stanford's 52-31 loss at Oregon, in which it allowed LaMichael James to rush for 257 yards and Darron Thomas to rack up yards with his arm (238 passing) and his legs (117 rushing), one of the most promising aspects of the Cardinal's 4-0 start was the emergence of what appeared to be a formidable defense.

While the competition wasn't exactly stiff, Stanford blanked UCLA in the Rose Bowl and kept Notre Dame out of the end zone until late in the fourth quarter. For a team that ranked ninth in the Pac-10 in total defense and 110th in the nation in pass defense last year, it was something for fans and players alike to be excited about. After the defense carried Stanford against the Fighting Irish, Andrew Luck told reporters:

"I don't want to go into comparisons with last year's defense, but I think guys grew up a lot. A lot of guys got playing experience last year and are really coming into their own. They have a tenacity and a chip-on-their-shoulder attitude."

Well I do want to go into comparisons with last year's defense. The chip on the Cardinal's shoulder likely grew a little larger thanks to Chip Kelly, whose Ducks gained 626 yards against a Stanford unit that entered the game ranked 11th in the nation in total defense. While it's an inexact comparison, comparing the Cardinal's stats through five games last season to its stats through five games this season suggests that the defense has improved under new coordinator Vic Fangio. (Stats after the jump.)

Stats are through five games; national ranking in parentheses.

As you can see, Stanford's pass defense was respectable through five games in 2009 before falling apart against bettter offenses. The Cardinal would allow 705 total yards passing in its next two games--losses at Oregon State and Arizona--and an average of 298 yards through the air in its final eight games of the season.

This year's defense will have an opportunity to make a statement Saturday against a USC team that boasts the 13th-ranked offense in the nation. The Cardinal will look to prove that its second-half collapse against Oregon was an aberration, or, perhaps, that Darron Thomas and LaMichael James are just really, really good and the Ducks are apt to hang 50 on anyone. (We may not know the answer to that until Oregon hosts Arizona on Nov. 26.)

I'm convinced the Stanford defense is better this season. How much better? I'm on the fence between a little and a lot. A solid effort against the Trojans could sway me.