Early enrollees to watch during spring practice

For additional spring practice coverage, check out the March 4, 2013, issue of Sports Illustrated. Buy the digital version of the magazine here.

In retrospect, Alabama running back T.J. Yeldon's remarkable freshman season shouldn't have come as a surprise. It's not just that he was a five-star prospect. It's not just that he rushed for 2,193 yards and 31 touchdowns as a senior at Daphne (Ala.) High in 2011. It's that on April 14, 2012, Yeldon torched Bama's defense -- the same unit that would go on to lead the nation in rushing defense, scoring defense and total defense -- for 179 all-purpose yards and a touchdown during the program's annual A-Day game.

Yeldon wasn't the only one true freshman to break out last spring. Tide wideout Amari Cooper, Georgia running back Keith Marshall and Florida offensive lineman D.J. Humphries also offered glimpses of what they could do. With that in mind, here are 10 early enrollees, listed alphabetically, to keep an eye on in 2013.

CB Eli Apple, Ohio State

Like many Urban Meyer recruits, Apple was a model of versatility in high school. He played defensive back, wide receiver and Wildcat quarterback during his senior year at Eastern High in Voorhees, N.J. Now, his natural timing and ball skills could warrant immediate playing time in Columbus. Apple and fellow early enrollee Cameron Burrows should be in the mix to help replace graduating cornerback Travis Howard, last season's Big Ten leader in interceptions. Meyer hasn't shied away from using young talent in the secondary before: Cornerback Joe Haden started 12 games as a true freshman at Florida after enrolling early in January 2007.

S Su'a Cravens, USC

USC withstood a barrage of bad press during the run-up to National Signing Day, and understandably so: A rash of decommitments battered the Trojans' class, headlined by blue-chip cornerback Jalen Ramsey's late flip to Florida State. It also made it easy to forget Lane Kiffin already secured seven early enrollees, four of whom were tabbed as five-star prospects. While quarterback-in-waiting Max Browne may be headliner of the group, Cravens is best positioned to contribute immediately. The USA Today All-USA Defensive Player of the Year collected 97 tackles as a senior and should replenish a secondary that lost T.J. McDonald, Nickell Robey and Jawanza Starling in the offseason.

LB Deoundrei Davis, Texas

Texas' linebacking corps took a step backward in 2012, shouldering part of the blame as the Longhorns finished 73rd in the nation in scoring defense. But while Jordan Hicks is set to return from a hip injury and Steve Edmond, Peter Jinkens and Dalton Santos have another year of experience under their belts, Davis might be too talented to keep off the field. The Cypress, Texas, native is both versatile -- he played safety and linebacker from his sophomore through senior seasons -- and naturally gifted. He's also already demonstrated his dedication to the program. He committed to Mack Brown less than 24 hours after receiving a scholarship offer last February.

OT Steve Elmer, Notre Dame

Offering significant playing time to a true freshman offensive lineman is never ideal, but given Notre Dame's situation, Elmer could make a compelling case. Starters Mike Golic Jr. and Braxston Cave are gone from the 2012 squad. Elmer was named the Anthony Muñoz Lineman of the Year at the U.S. Army All-American Bowl. And by enrolling early and taking part in spring practice, Elmer will have an opportunity to earn Brian Kelly's trust. If nothing else, he's smart enough to cut it in South Bend; he graduated from Midland (Mich.) High in December with a 4.3 GPA.

RB Derrick Henry, Alabama

As a true freshman in 2009, Trent Richardson split carries with Mark Ingram and rushed for 751 yards and eight touchdowns to help Alabama win the national title. As a true freshman in 2012, Yeldon split carries with Eddie Lacy and galloped for 1,108 yards and 12 scores to help the Tide secure the BCS crown. Henry could become the next back in that lineage. The Yulee, Fla., product is the all-time career rushing leader in high school history with 12,212 yards, and he could challenge SEC defenses with his imposing 6-foot-3, 243-pound frame. He'll get a jump on fellow 2013 running back recruits Altee Tenpenny, Alvin Kamara and Tyren Jones, who won't arrive in Tuscaloosa until the fall.

TE O.J. Howard, Alabama

Howard is Henry's roommate at Bama, and perhaps fittingly, he also has a good shot to see early action. The Tide lose Michael Williams and Kelly Johnson, their two most experienced tight ends from last year's championship team. Nick Saban has shown a willingness to turn to talented true freshmen pass-catchers like Cooper, and Howard's early arrival in Tuscaloosa gives him extra time to learn the offense. It also doesn't hurt that Howard's size, athleticism and playmaking ability could make him an instant red zone favorite for quarterback AJ McCarron. The 6-6, 250-pounder racked up 854 yards of total offense and 12 touchdowns as a senior at Autauga Academy in Prattville, Ala., despite missing four weeks to a knee injury.

DE Shaq Lawson, Clemson

Though Tajh Boyd and Clemson's offense get all the attention, Brent Venables' pass rush took major strides in 2012. The Tigers recorded 34 sacks, 22nd in the nation, and held LSU to just 219 total yards in a Chick-fil-A Bowl victory. But defensive end Malliciah Goodman is gone, and Lawson could emerge as his most serviceable replacement. The latter certainly has the ideal build: Lawson is listed at 6-4 and 260 pounds and recorded 23 tackles for loss in 2011 before spending last year at Hargrave Military Academy in Chatham, Va.

S Tray Matthews, Georgia

A Georgia commit since August 2011, Matthews is one of 13 early enrollees in Athens. He's also the one most likely to leave a lasting impression this spring. Matthews is a physical player who made four tackles in this year's U.S. Army All-American Bowl, and his 6-foot, 194-pound frame is already in SEC shape. He'll also have a chance to immediately fill an area of need: Bacarri Rambo and Shawn Williams, who combined to make 66 starts, both wrapped up their Bulldogs' careers at the end of last season.

DE DeMarcus Walker, Florida State

Florida State ranked second in the nation in total defense in 2012, thanks primarily to a defensive line that featured Bjoern Werner and Tank Carradine. But both are moving to the NFL this spring. Now, the 'Noles need some fresh faces to step up. Enter Walker, a one-time Alabama commit who flipped to FSU on the night of the BCS title game. He has all the makings of an immediate contributor. He has college-ready size (6-3, 265 pounds) and speed (he runs a 4.6 40-yard dash, according to 247Sports.com), and he boasts a strong relationship with new Florida State defensive coordinator Jeremy Pruitt.

WR JaQuay Williams, Texas A&M

A touted prospect in the 2012 cycle, Williams attended prep school last year after failing to meet NCAA entrance requirements. By waiting a season to break onto the college scene, he could be primed to make an immediate mark. The 6-3, 195-pounder is dangerous both down the sideline and over the middle, and he could help fill the void left by Ryan Swope and Uzoma Nwachukwu, a receiving tandem that combined for 15 touchdowns for the Aggies last season. By enrolling early, Williams will also have time to establish a rapport with Johnny Manziel; Williams will have all of spring practice to get a leg up on Ricky Seals-Jones and Laquivonte Gonzalez, prized wideout recruits set to join him in College Station in the fall.

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