TUSCALOOSA, Ala. -- Here is what we know: Alabama has won two of the past three national championships because of defense.
In 2009 Alabama had the nation's No. 2 defense and beat Texas in Pasadena to finish 14-0.
In 2011 Alabama had the nation's No. 1 defense and beat LSU 21-0 in New Orleans for the BCS title.
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Here is something else we know: Those two defenses had a lot of really good players. After each championship season six of the starting 11 were taken in the next NFL Draft.
But here's something you may not know: For all of the brute strength, overwhelming size, and blinding speed of Alabama's defense in the Nick Saban era (2007-present), it has also been successful because it is one of the most precisely taught units in all of college football. And nowhere is this precision and attention to detail greater than in the secondary.
Why? Because that position is coached by Saban himself.
"Coach Saban can look at you and know if you are one inch out of position," senior safety Robert Lester said. "That one inch means the difference in getting beat by a receiver and having enough help to cover him. What we do is incredibly detailed."
While Alabama will certainly miss linebackers Dont'a Hightower (No. 25 pick) and Courtney Upshaw (No. 37 pick), the key to Alabama's fortunes on defense in 2012 will be the ability of Saban and defensive coordinator Kirby Smart to successfully rebuild the secondary.
Three of four starters are gone. Safety Mark Barron and cornerbacks DeQuan Menzie and Dre Kirkpatrick each made at least one All-America team last season. Barron (No. 7) and Kirkpatrick (No. 17) went in the first round of the draft. Menzie, the most athletic corner Alabama had, was a steal in the fifth round.
|Alabama defenders taken in NFL Draft|
|Name||Pos.||Draft No. (Team)|
|Mark Barron||S||7 (Tampa Bay)|
|Dre Kirkpatrick||CB||17 (Cincinnati)|
|Dont'a Hightower||LB||25 (New England)|
|Courtney Upshaw||LB||37 (Baltimore)|
|Josh Chapman||DT||136 (Indianapolis)|
|DeQuan Menzie||CB||146 (Kansas City)|
"We had the best secondary in the country last season. No doubt about it," said Dee Milliner, who shared the corner with Menzie and returns for his junior season. "But I believe if we work at it, this group has a chance to be as good."
When I sat down with him on Tuesday, Saban said this secondary is very much a work in progress.
"We've had lots of really good players at that position and fairly good depth," Saban said. "We still have good players. But are these guys going to play as well as the ones who had 30 career starts? Probably not. But those veteran guys made mistakes earlier in their careers. To me you just have to have patience in the development of the players that you have."
It is an interesting collection of talents and personalities that Saban and Smart must mold into a unit that thinks with one brain: Lester, a senior, was a second team All-American in 2010 when he intercepted eight passes. He wasn't challenged as much last season, quite frankly, because Alabama was so good up front.
"Robert took advantage of every opportunity that came his way two years ago," said Saban. "Last year he didn't have as many chances because we were forcing people to get rid of the ball pretty quickly. He made some plays but he also missed some."
Milliner had 11 starts at cornerback in 2010. But in 2011 a healthy Menzie earned the starting job in Alabama's base defense. But Milliner was on the field on the vast majority of plays because Alabama played so much nickel defense.
Those two positions are locked down. The other safety spot will be contested between sophomores Vinnie Sunseri and Ha Ha Clinton-Dix. Sunseri, the son of Tennessee defensive coordinator Sal Sunseri, appears to have the edge after making a big impression as a freshman on special teams and as a sixth defensive back. Clinton-Dix also played in all 13 games last season.
"Never seen anyone work as hard as Vinnie," Lester said. "He's a perfectionist. He is definitely a coach's son."
Saban brought in a pair of junior college transfers -- Deion Belue and Travell Dixon -- to compete with junior John Fulton for the other cornerback job. It looks like Belue will be the starter.
"Deion is a good cover guy, but we need for him to be a little better in run support," said Saban.
It is a very good collection of players, but it's going to be difficult to touch the 2011 secondary. Consider this stat: Last season teams averaged only 4.3 yards per passing attempt as Alabama led the nation in pass efficiency defense. In fact, only two teams in the country (Alabama, South Carolina) gave up less than five yards per passing attempt.
"That's the lowest total that one of our defenses have ever had," Saban said. "What it means is that the ball is not getting thrown down the field that much. So the safeties like Robert [Lester] are just not getting as many opportunities. That's a good thing."
Alabama gave up only six touchdown passes last season. Only two other schools in the country (LSU, Rutgers) gave up single digits in touchdown passes.
It remains to be seen if there are three NFL Draft choices in this group. But Saban believes that a differential in talent from one year to the next can be overcome by drilling players to run the defense exactly as it has been designed with no margin for error.
"I learned all of this in the NFL," Saban said. "The players are so good and you're not really better than the other guy. So you better be precise so that you're not putting yourself at a disadvantage. Where you position guys on the field makes a huge difference in how you cover people."
Then he paused for a second.
"Still, you've got to have great players no matter how well you teach it."
Here lately, that hasn't been a problem at Alabama.
The Tony Barnhart Show begins Aug. 28 on The CBS Sports Network.