GAINESVILLE (CBSMiami/AP) – The Southeastern Conference built its well-deserved reputation on the back of fearsome, fast, talented defenses. It’s led the conference to seven straight national championships, but it’s largely disappeared this year.

Nine of 14 SEC teams are surrendering more yards than a year ago at this time. Among them are some of the conference’s defensive leaders the past few seasons: Alabama, LSU and South Carolina.

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The reason behind the decline is not obvious. It could be the proliferation of spread offense, an exodus of defensive talent to the NFL, or new coaches pushing offensive tempo to the red.

Alabama coach Nick Saban said the defensive slide could simply be about talent.

“There’s a lot of explosive players on offense,” Saban said, “and maybe there’s not as many dominant defensive players.”

Saban’s top-ranked and two-time defending champion Crimson Tide outlasted Texas A&M 49-42 two weeks ago in a shootout that was nothing like the, 9-6 overtime defensive slugfest against LSU in 2011.

Then again, it’s hard to stop anybody when the league’s best defenders have moved on.

Former Georgia linebacker Jarvis Jones led the SEC with 14 ½ sacks, 24 ½ tackles for loss and seven forced fumbles a year ago and is now causing havoc for the Pittsburgh Steelers. Alabama cornerback Dee Milliner, the 2012 league leader in passes defended, was among four Crimson Tide defensive starters selected in the NFL draft last spring.

LSU had seven defensive players off last year’s team drafted. With just three starters back on defense, the yards and points the Tigers allow have nearly doubled from a year ago. LSU was giving up 149 yards and 10 points through four games in 2012; it is yielding 310 yards and 19.5 points this season.

Tigers coach Les Miles said it’s not about a lack of talent, it’s about experience.

“Our players are as talented as we’ve ever had and I think there’s a maturity that needs to take place so they can play with their cleats headed north and south, and ready to make a tackle,” Miles said.

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But even veteran players are struggling to make an impact.

South Carolina All-American defensive end Jadeveon Clowney, the reigning SEC defensive player of the year, was expected to dominate after notching 13 sacks a year ago and sending the helmet of Michigan runner Vincent Smith flying off in the Outback Bowl last New Year’s Day.

The Gamecocks lost five senior linebackers off last year’s team and Clowney’s seen offenses run away from his side. The Gamecocks, 11th in the country defensively a year ago, have allowed 76 points, nearly three times the 29 they gave up through three games in 2012.

Clowney has 10 tackles and two sacks this year. Gamecocks coach Steve Spurrier even joked that Clowney better get in shape this week because it’ll be a hot day in Orlando when No. 12 South Carolina faces UCF on Saturday.

“It’s hard, man,” said Chaz Sutton, the Gamecocks’ other starting defensive end. SEC teams “have a lot of great guys at the skill positions that can fly and tear the top off a defense.”

Things could get worse for SEC defenses.

The league’s leading defensive unit in Florida — the Gators have permitted fewer than 15 points and 213 yards a game so far this year — could be without star lineman Dominique Easley, who injured his knee in practice and indicated on Twitter that he’s out for the season.

And it doesn’t look like SEC offenses will slow down anytime soon.

South Carolina quarterback Connor Shaw has his team’s offense operating at a record-setting pace so far at nearly 480 yards a game. Despite the success, he thinks SEC defenses are as tough as ever even if the statistics don’t bear that out.

“I know that all the teams are putting up big numbers,” he said. “But I still think defense is going to win the championship in the SEC.”

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