ESPN College Football

Posted by ESPN.com's Chris Low

Every team in the SEC has holes to fill next season, even defending national champion Florida.

Some spots are greener than others. So in keeping with our St. Patrick's Day theme, here's a breakdown of the greenest units on each of the 12 teams:

Alabama: The Crimson Tide are replacing three-year starter John Parker Wilson at quarterback, but losing the threesome of Andre Smith, Marlon Davis and Antoine Caldwell on the offensive line leaves the biggest void. They were at the crux of just about everything Alabama did on offense last season.

Arkansas: The Razorbacks were frighteningly young last season on defense, so just about everybody is back who made a tackle. They still need more playmakers in the secondary, though, which is where heralded cornerback signee Darius Winston comes in.

Auburn: The truth is that everybody in college football is looking for more defensive tackles. But with Tez Doolittle out of eligibility and Sen'Derrick Marks leaving early for the NFL draft, the Tigers could use some more muscle up front.

Florida: It's stating the obvious that Percy Harvin was the ultimate difference-maker on offense, but Louis Murphy really came on last season, too. Both are gone now, and the Gators need a go-to threat to emerge at receiver.

Georgia: Much of the focus this spring will be on Joe Cox and the quarterback position, but the Bulldogs' most glaring weakness is the lack of a dominant pass-rusher from the defensive end position. They've got to find somebody who can consistently get to the quarterback.

Kentucky: The Wildcats' running back stable took a huge hit. The only guy they know for sure that will be back next season and be 100 percent is senior Alfonso Smith. Junior Derrick Locke suffered a serious knee injury in the bowl game, and junior Moncell Allen was an academic casualty for the bowl game.

LSU: Jordan Jefferson started the final two games at quarterback last season as a true freshman and enters 2009 as the favorite to win the job. His main competition will come from another true freshman, Russell Shepard, who graduated early and is going through spring practice.

Mississippi State: First-year coach Dan Mullen took a look at the Mississippi State roster soon after being hired and made it clear that the Bulldogs needed to add receivers. They loaded up on receivers in this signing class, and several of them could play key roles next season.

Ole Miss: Instead of one unit, we'll go with one position at Ole Miss. Michael Oher was such a force at left tackle for the Rebels that it's going to be difficult for anyone to fill his shoes. Sophomore Bradley Sowell moves over after being used as a blocking tight end last season, and touted signee Bobby Massie arrives this summer.

South Carolina: The Gamecocks lost four of their top six defensive backs from a year ago, including their top three cornerbacks. Don't be surprised if true freshmen Stephon Gilmore and DeVonte Holloman play major roles in 2009 and end up starting at some point. Either way, it's going to be a young South Carolina secondary.

Tennessee: There's nothing resembling any depth at offensive tackle for the Vols. Chris Scott will line up at left tackle, and he's probably better suited to play guard. Redshirt freshman Aaron Douglas could end up being the starter at right tackle, and Douglas came to Tennessee as a tight end.

Vanderbilt: With Justin Wheeler going down last week with a knee injury that will cause him to miss the 2009 season, the Commodores are really hurting at receiver. It's more important than ever now that Connecticut transfer Terence Jeffers is eligible in the fall.