When the old alma mater's football team hired Todd Grantham to coach the defense, I thought Bobby Petrino had lost his mind.

Plenty of Georgia fans, and some colleagues in the media, told me Grantham can’t coach. Some of those same people were praising Grantham not too long before that. But, hey, I figured maybe he’d just lost his touch rather than the criticisms being a case of fickle fans looking for a scapegoat and media types not liking Grantham's prickly personality.

But well, now, look at that: Louisville ranks No. 3 in the country in total defense. The Bulldogs are No. 36. Louisville is No. 8 in scoring defense; Georgia is No. 50.

The Cardinals are winning with defense as Petrino’s offense sputters like it never has thanks to a bad offensive line and green quarterbacks (miss you, Teddy Bridgewater). The Bulldogs are winning in spite of their defense--at least for now.

Something isn't adding up here. How can the incompetent Grantham field a better defense than the beatified Jeremy Pruitt?

It's funny how fandom works. Georgia's defense is still shaky yet Pruitt escapes criticism for the most part. It was comical to see Pruitt remind fans they should be scrutinizing his unit for the loss at South Carolina instead of obsessing over Mike Bobo's play-calling.

I heard lots of complaints that Grantham’s defense is too complicated but Pruitt’s simplified scheme is getting no better results. Bulldogs fans who grew tired of confused play in the secondary under Grantham now shrug off the same thing because, well, Pruitt needs more time to get his recruits in there.

Grantham has needed no such excuses at Louisville. The Cardinals lost two first-round draft picks on defense from last season: safety Calvin Pryor and linebacker Marcus Smith, a Columbus native. Linebacker Preston Brown, a third-round pick, starts for the Bills. Grantham changed the base defense to a 3-4 from a 4-3. The defense has constantly been put in terrible positions because of turnovers deep in Louisville’s end.

And yet even with all of those factors working against him, Grantham has fashioned a dominant unit. Louisville’s defense has hardly missed a beat after Charlie Strong built up that side of the ball with good recruits.

Remember when Petrino critics pounced on that (thinly-sourced) report about him feuding with Grantham? The one that said Petrino wanted to fire Grantham but was "stuck" with him?

Here's what Petrino said after the Cardinals beat Wake Forest 20-10 on Saturday with the defense carrying them again (Wake's only touchdown was a fumbled recovered in the end zone): "Thank God we have a great defense, because it's allowing us to work at getting better offensively."

Clearly there's lots of tension between those coaches.

I've been around these parts long enough to know what comes next. The three letters that are used as an argument unto themselves, with no further elaboration needed: S-E-C, S-E-C. The SEC is so superior its teams win all the bowl games that matter and lose them only when they don't care.

Kidding aside, the SEC clearly is a better league than the ACC at the top and Louisville has yet to play Clemson and Florida State. So I direct you to Football Outsider and its S&P defensive ratings. It's a metric that looks at success rate, explosive plays, drive efficiency and an opponent adjustment "designed to reward tougher schedules and punish weaker ones."

The Cardinals rank fourth nationally in defensive S&P. The Bulldogs are No. 44.

Any way you slice it, Louisville has a very good defense with Grantham and Georgia’s defense is not very good with Pruitt. The Cardinals are fast, physical, and sound. The numbers say they are legit and they look the part.

But who I am going to believe on Grantham: reactionary Bulldogs fans and critical media, or my lying eyes?