ALABAMA

Who replaces Blake Sims? Nick Saban faced this question last year after AJ McCarron headed to the NFL. Sims mostly played well in his only season as the Crimson Tide's starting QB, although he had Amari Cooper and an outstanding running game to help him out.

Folks thought FSU transfer Jacob Coker would supplant Sims at some point, but he never did.

And now it appears that redshirt freshman David Cornwell is pressing Coker, maybe even surpassing him for the starting QB job.

Coker has thrown for 698 yards with five touchdowns in 18 career games and Cornwell was an Elite 11 prospect out of Oklahoma who enrolled early in 2014.

Alec Morris played in four games last year, but didn’t throw a pass and highly touted freshman Blake Barnett enrolled early, but no freshman has ever started at QB under Saban at Alabama.

ARKANSAS

Who replaces Trey Flowers? Deatrich Wise Jr. is " athletic, strong and a very, very powerful kid," coach Bret Bielema said this spring.

He’s ready to turn Wise, who is 6-foot-5, 271 pounds, loose on quarterbacks as Arkansas moves on without Flowers, who was selected by New England, and defensive tackle Darius Philon, who was picked by San Diego.

Wise played in 10 games as a sophomore in 2014, with 13 tackles and two sacks.

“The only person who will limit Deatrich Wise is Deatrich Wise,” Bielama said in April. “As we go out on the road and recruit defensive ends, you can’t get any better than that.”

He’ll be part of a deeper defensive line that also will include returning starters JaMichael Winston (6-4, 272), who also impressed coaches this spring, and Taiwan Johnson (6-2, 273), who had eight tackles for loss and 4½ sacks last fall.

AUBURN

Who replaces Reese Dismukes? Let's get this right.

A walk-on without a scholarship who sat out last season and just switched positions is in line to replace an All-American at center.

Yeah, that’s right.

To be fair, Austin Golson transferred from Ole Miss, where he played 12 games at guard in 2013 and was considered the starter at right tackle for the Rebels after spring 2014.

But the native of Prattville, Ala., walked on at Auburn to be closer to his grandparents and hadn’t been awarded a scholarship as of earlier this month.

Golson had to sit out last year because of NCAA transfer rules and then moved to center in December.

Auburn offensive line coach J.B. Grimes has said Golson, who is 6-5, 310 pounds, has NFL potential.

Golson is competing with Xavier Dampeer.

FLORIDA

Who replaces Dante Fowler Jr.? What is a redshirt freshman from Casper, Wyo., doing at Florida?

Trying to take the place of the third overall pick in the NFL draft.

After the Gators plucked Taven Bryan out of Wyoming in 2014, he redshirted last fall while he learned technique and schemes.

He then excelled this spring.

“That’s my big Wyoming wild man,” defensive line coach Chris Rumph told gatorzone.com, the athletic program’s web site. “He’s a big old caveman and wants to use all his brute strength.”

At 6-5, 275, Bryan has the size to play both tackle and end, and first-year coach Jim McElwain has mentioned him playing fullback, if needed.

“Taven’s gonna do so good, I’m trying to tell you man,” defensive end Alex McCalister told gatorzone.com.

KENTUCKY

Who replaces Bud Dupree? Some folks might consider it impossible to replace a player so versatile and talented as Dupree, who Pittsburgh selected with the 22nd pick of the NFL draft.

Jabari Johnson (6-1, 276), who went to Stephenson High, might be able to provide the pass rush of Dupree, who had a combined 20 sacks and tackles for loss last fall, and Jason Hatcher (6-3, 242) was a protégé of Dupree the past two years.

Hatcher had 5½ tackles for loss last season and is moving around a lot in Kentucky’s 3-4 scheme, much like Dupree did.

“Jason’s a guy that I’m really excited about. … ” Kentucky coach Mark Stoops said this spring. “He’s very explosive. He’s always been a great pass rusher. He’s getting more and more comfortable on his feet and more and more versatile.”

LSU

Who replaces Jalen Collins? From one Jalen to the next.

Jalen Mills appeared to be headed to the NFL this spring, much like fellow defensive back Jalen Collins (the Falcons’ second-round pick), but Mills decided to stay at LSU, where he’ll be the leader of the defensive backfield this fall.

He’ll also attempt to continue the legacy of LSU’s defensive backs. The program claims it’s “DBU” — or Defensive Back University — boasting recent players like Eric Reid, Tyrann Mathieu and Collins.

Mills, who moved from cornerback to safety, has started all 39 games in his three years at LSU and was seventh on the team with 62 tackles in 2014.

He’s learning new defensive coordinator Kevin Steele’s defense and is expected to team with cornerback Tre’Davious White and Ed Paris, and safety Jamal Adams for LSU’s newest edition of “DBU.”

OLE MISS

Who replaces Senquez Golson? It's tough to replace a player as important as Golson was for the Ole Miss defense last season.

Tee Shepard is being projected as the kind of player who can fill the void at cornerback left by Golson.

He’s been around, having signed with Notre Dame as a top prospect in 2012, but he transferred to Holmes Community College and then to Ole Miss.

Shepard likely would have started opposite Golson last year, but missed the season with a toe injury. He intercepted the final pass of the spring game.

“He’s going to be one of those breakout guys, I think,” former Ole Miss safety Cody Prewitt told the Jackson (Miss.) Clarion-Ledger.

Tony Bridges, who is a junior, also was a top prospect out of Mississippi Gulf Coast College and is expected to team with Shepard at cornerback.

MISSISSIPPI STATE

Who replaces Preston Smith? Ryan Brown (6-6, 262) started opposite Smith, who went to Stephenson, last year and could make the leap forward after finishing with 3 1/2 sacks in 2014.

The Bulldogs will need increased production from him or A.J. Jefferson to replace Smith, who was drafted by Washington in the second round.

“(Brown) knows, it’s like baseball. He’s going into the No. 4 spot in the lineup,” defensive coordinator Manny Diaz told the Jackson Clarion-Ledger. “So he might have had good production batting fifth or first, but now he’s a guy we’re expecting to hit the home runs.”

Jefferson (6-3, 270) played in all 13 games last year, gaining plenty of experience behind Smith.

He finished with seven tackles for loss and 2½ sacks in 2014, and made one of the best plays in the spring game when he powered through an offensive lineman and dumped a running back for a loss.

MISSOURI

Who replaces Shane Ray? If LSU is "DBU," then Missouri is becoming "DLU."

Sheldon Richardson, Michael Sam, Kony Ealy, Markus Golden and Ray are among the defensive linemen who have excelled for the Tigers the past few years.

Look for sophomore Charles Harris, who is 6-3, 255 pounds, to join that group. He had 3 1/2 sacks in spring scrimmages and picked off a pass, returning it for a TD.

Coaches are moving Harris around, sometimes playing him as a stand-up end and sometimes dropping him in coverage.

The Tigers are looking at him replace Ray, who was Denver’s first-round pick, and Golden, Arizona’s second-round selection.

Harris, who had two sacks while backing up both of them last fall, was projected to team with Marcus Loud (6-4, 260), but he was dismissed from the program on Wednesday.

SOUTH CAROLINA

Who replaces Mike Davis? Brandon Wilds has his chance.

He’s waited behind Davis, a fourth-round pick of San Francisco, for three seasons and will finally get his opportunity to be the Gamecocks’ No. 1 running back.

He has the experience, even starting four games in 2014, when he finished with 570 yards and four touchdowns, to go with 18 catches for 143 yards and another score.

At 6-2, 224, Wilds is larger than Davis (5-9, 217), but is facing competition from sophomore David Williams, who often worked with the first-team offense during spring drills.

Wilds has 1,277 career yards and Williams (6-1, 216) rushed for 256 yards in 2014.

“There’s a big running back competition, and I respect Dave to the utmost,” Wilds said this spring. “He reminds me of a great running back. We are coming out here competing every day.”

TENNESSEE

Who replaces A.J. Johnson? Johnson was a tackling machine for more than three years, so his suspension in November left a massive hole in the defense.

Freshman Jakob Johnson had to make his first start against Missouri on Nov. 22 and finished the season at the position.

Dillon Bates, the son of former Tennessee safety Bill Bates, could win the starting position.

He missed all but four games last year after tearing his labrum against Georgia and wasn’t available to plug the void.

With Jakob Johnson out with a shoulder injury and early enrollee Darrin Kirkland Jr. (torn pectoral) out this spring, Bates (6-3, 230) and Kenny Bynum saw most of the action at middle linebacker this spring.

“We continue to still be a work in progress at the linebacker position,” coach Butch Jones said earlier this month.

TEXAS A&M

Who replaces Cedric Ogbuehi? Like defensive linemen at Missouri, the Aggies have produced outstanding left tackles such as Luke Joeckel, Jake Matthews and Ogbuehi, all first-round picks in the past three years.

Avery Gennesy and Germain Ifedi are competing to replace Ogbuehi this season, but Ifedi (6-5, 325) started at right tackle last year and the Aggies could decide to keep him there.

If the coaching staff does that, expect Gennesy (6-5, 305), who redshirted in 2014, to protect quarterback Kyle Allen (or Kyler Murray) from the left side.

Gennesy, who transferred from East Mississippi Community College, and Ifedi practiced at both positions this spring.

“I think Avery Gennesy and Germain Ifedi are really, really solid tackles for us,” coach Kevin Sumlin told 247Sports.

VANDERBILT

Who replaces Vince Taylor? Taylor was the anchor of Vanderbilt's defense at tackle in coach Derek Mason's 3-4 scheme, so it's critical the Commodores find a replacement for him.

That’s where Jay Woods (6-3, 283), a sophomore from Jackson, comes in.

Woods shined this spring at defensive tackle after putting on the pounds and moving from end, where he had 31 tackles and 1½ tackles for loss in 12 games last fall.

He had a season-high five tackles against Georgia.

If Woods stays at end or rotates between the two positions, expect Adam Butler (6-5, 305) or Nifae Lealao (6-5, 320) to see snaps at nose tackle.

With Caleb Azubike at the other end position and a strong group of linebackers, Vanderbilt could have a formidable front seven in 2015.