The weakest position group for each top 25 team

Alabama's Damien Harris is the back with the most carries and yards, but there's no guarantee he'll win the job, while Oregon is hoping Montana State transfer Dakota Prukop is the second coming of Vernon Adams Jr. AP Photos

Mark Schlabach's 2016 Way-Too-Early Top 25 has Alabama and Florida State in the top two spots, but each team has big questions to answer this spring.

Using those rankings, here is the weakest position group for each of our top 25 teams.

1. Alabama Crimson Tide

Running back: This isn't a knock on Alabama's running backs. They're just unproven. Damien Harris has the most carries (46) and yards (157) of any returning player, but he has barely scratched the surface. And some believe Bo Scarbrough is the favorite to win the job, but he got even less touches this past season. Plus, he has had two major knee injuries going back to high school. It's Alabama. The Tide are going to find somebody to run the ball. But after losing both Derrick Henry and Kenyan Drake, the backfield will be a major question mark heading into the season. -- Greg Ostendorf

2. Florida State Seminoles

Linebacker: A combination of attrition of underclassmen the past few years and the loss of two longtime starters in Reggie Northrup and Terrance Smith makes linebacker the clear weak spot on an otherwise talented Florida State defense. The Seminoles do get star-crossed phenom Matthew Thomas back, and if he finally blossoms after years of injuries and off-field problems, there may be limited drop-off. Ro'Derrick Hoskins also has a half-dozen starts under his belt. If Thomas proves to be an answer, that may leave wide receiver as FSU's biggest worry. The unit is filled with talent, but no No. 1 has truly emerged, and inconsistency from this group frustrated Jimbo Fisher all season in 2015. -- David M. Hale

3. Michigan Wolverines

Linebacker: The Wolverines lost all three starters in the middle of the defense last year. Their replacements may be an upgrade athletically -- especially if Jabrill Peppers' move from safety to outside linebacker is permanent -- but that doesn't solve a major experience problem. Senior Ben Gedeon is the only player on the roster who has started a game at linebacker. They'll need to be well-versed in the playbook to take full advantage of Don Brown's aggressive game plan this fall. -- Dan Murphy

4. Baylor Bears

Defensive line: Last season, Baylor featured the best defensive line under Art Briles. Problem is, every starter from that unit is now gone, including co-Big 12 Defensive Player of the Year Andrew Billings. The Bears will have to start from scratch again up front defensively. -- Jake Trotter

5. Clemson Tigers

Safety: It's going to be a rebuilding job on defense for the second year in a row for coordinator Brent Venables, but while he's high on his young talent at defensive end, linebacker and corner, the safety position is a serious concern. Three underclassmen -- Jayron Kearse, T.J. Green and nickel corner Travis Blanks -- all departed early for the NFL draft, leaving Venables with some big holes to fill and limited depth from which to draw. Jadar Johnson and Van Smith both have experience as backups, but will now step into a starting role with virtually no established depth behind them. "We've got to grow some guys up quick," Venables said. -- David M. Hale

6. LSU Tigers

Linebacker: One of LSU's best players -- Kendell Beckwith -- plays linebacker, so the position is not especially weak. The concern is that linebacker has the most uncertainty and the shakiest depth. If new defensive coordinator Dave Aranda runs predominantly 3-4 looks, who fills the spots inside and on the edge? Senior Duke Riley and junior Donnie Alexander could play expanded roles this season, and don't be surprised to see a true freshman such as Michael Divinity on the field, either. -- David Ching

7. Oklahoma Sooners

Wide receiver: For the past two seasons, Sterling Shepard has basically carried the Oklahoma receiving corps. With Shepard gone, the Sooners don't have an obvious heir apparent to replace him as Baker Mayfield's go-to guy. -- Jake Trotter

8. Stanford Cardinal

Defensive line: The biggest loss might be that of longtime defensive line coach Randy Hart, who retired after 46 years as a full-time assistant coach in college football. Hart participated in 10 Rose Bowls as a player and coach and will undoubtedly be missed. His replacement, Diron Reynolds, was an assistant defensive line coach for the Minnesota Vikings (2009-2013) before serving under Hart at Stanford in 2014. Reynolds inherits an unproven group -- outside of Solomon Thomas -- that will need to replace Aziz Shittu and Brennan Scarlett. Harrison Phillips has played, too, but his health remains a question mark coming off a serious knee injury. Luke Kaumatule, who played from 2012-14, redshirted last season and will be expected to contribute at defensive end. -- Kyle Bonagura

9. Notre Dame Fighting Irish

Secondary: The Irish secondary said goodbye to safeties Elijah Shumate and Matthias Farley, along with cornerback KeiVarae Russell. What is left other than corner Cole Luke and safety Max Redfield is a question mark, and even Redfield remains a bit of an enigma after a thus-far underwhelming three-year career that includes a suspension from the Irish's bowl game last year. Drue Tranquill has shown promise at safety, but has had each of his first two seasons cut short due to ACL tears in each knee. Devin Butler came on strong late last season, but he broke his foot before the bowl game. Shaun Crawford had the starting nickel job locked up going into last season, but an ACL tear cost him his freshman season. One face to keep an eye on: Nick Watkins, a rising junior who impressed the staff by stepping up against Ohio State after Butler went down. As important for the secondary's development will be a mostly retooled front seven that struggled getting to the passer last season. -- Matt Fortuna

10. Ohio State Buckeyes

Secondary: Given all the coveted defensive backs the Buckeyes have piled up on the recruiting trail over the past few years -- including another this season in cornerback Jordan Fuller -- odds are that new co-defensive coordinator Greg Schiano will be able to keep that unit humming along at a high level. But after losing three starters with eligibility left to the NFL draft, Ohio State's most glaring question is just how quickly it can tap into all that inexperienced talent in the secondary. -- Austin Ward

11. Houston Cougars

Defensive back: It has been the Cougars' strength in recent years because of the veteran presence that existed there, but three of the Cougars' four 2015 starting defensive backs -- cornerback William Jackson III and safeties Adrian McDonald and Trevon Stewart -- were all seniors and are gone. Not only is there a lot to replace from a talent standpoint, but from a leadership role as well. McDonald and Stewart combined for 90 career starts between them, the most of any defensive players on the 2015 Cougars, and Jackson started 28 games. The Cougars also graduated defensive back Lee Hightower, who started 18 career games. They do have some experience returning (cornerback Brandon Wilson started 20 games and sophomore-to-be Jeremy Winchester spot started late last season), but replacing what they lost will be a challenge. -- Sam Khan Jr.

12. Tennessee Volunteers

Tight end: Tennessee is fine atop the depth chart at tight end -- junior Ethan Wolf has already started 23 games and totaled 513 career receiving yards -- but things get a bit less certain behind him. Wolf was the only Volunteers tight end to catch a pass last season, which is one reason why they are moving senior Jason Croom to the position this spring. Surely the 6-foot-5 converted wide receiver will bring more productivity to the position. -- David Ching

13. Ole Miss Rebels

Offensive line: Some teams on this list will have to replace a starter or two on the offensive line. Ole Miss has to replace all five starters from its Sugar Bowl victory. Among those is offensive tackle Laremy Tunsil, the likely No. 1 pick in next month's NFL draft. There are some exciting players returning, beginning with sophomore guard Javon Patterson. Greg Little, the nation's top offensive tackle, will also arrive this summer, but there's still a lot of work to be done before the Rebels open against Florida State. -- Greg Ostendorf

14. Michigan State Spartans

Offensive line: Weakest might be unfair given the way the Spartans have consistently performed in the trenches in recent history, but the offensive line is certainly the biggest question mark. Michigan State loses three starters up front, including All-Americans Jack Conklin and Jack Allen. Injuries last fall gave some younger guys a chance to get experience, but there are voids to fill up front on a roster that remains steady in most other places. -- Dan Murphy

15. TCU Horned Frogs

Running back: On paper, this looks like TCU's weak spot. The Frogs will replace the prolific Aaron Green with a committee of backs and are comfortable with their options. Kyle Hicks, Shaun Nixon and Trevorris Johnson all bring some experience to the table, and freshmen Sewo Olonilua (an early enrollee) and Darius Anderson could be difference-makers early on. -- Max Olson

16. USC Trojans

Defensive line: There are some reasons for optimism on the defensive line -- the Trojans have signed nine defensive linemen over the past two seasons -- but USC is really light on experience. True freshmen Noah Jefferson (14 games), Rasheem Green (14 games) and Jacob Daniel (3 games) all played last year, while Kevin Scott and Christian Rector redshirted. USC's most important addition in its recent recruiting class was that of Oluwole Betiku, the nation's No. 8-ranked defensive end, who should be expected to make an impact from Day 1. The line will be coached by former USC All-American Kenechi Udeze, who was elevated from assistant strength and conditioning coach to serve on new defensive coordinator Clancy Pendergast's defensive staff. -- Kyle Bonagura

17. Iowa Hawkeyes

Defensive line: There's no good answer here as Iowa returns multiple starters at every position group. But on the D-line, particularly on the edges -- if Drew Ott loses his case with the NCAA for a hardship waiver -- the Hawkeyes will be without their top two players from a year ago among the front four. Iowa may struggle to pressure the QB, even with starters Jaleel Johnson and Nathan Bazata back at tackle. A weak unit? No, but it's one with more questions than the other groups. -- Mitch Sherman

18. North Carolina Tar Heels

Linebacker: The linebacking corps will need some reworking after the graduations of Shakeel Rashad and Jeff Schoettmer. The two last year were the Tar Heels' second- and third-leading tacklers, respectively. Let's not forget that, even with these two in the fold, UNC was atrocious against the run, finishing 122nd nationally in opponents' rushing yards per game (247.36) and 109th in opponents' yards per rush (5.13). The defense as a whole figures to make a big leap in Gene Chizik's second year as coordinator, though, after he turned the D around last year en route to an 11-3 season. Expect sophomore Andre Smith and junior Cayson Collins to emerge as the central pieces of the linebacking corps -- in the middle and on the outside, respectively. -- Matt Fortuna

19. Georgia Bulldogs

Wide receiver: As tempting as it is to pick quarterback or offensive line, wide receiver is probably Georgia's most unproven position group. Following Malcolm Mitchell's departure for the NFL, the Bulldogs return seven wideouts who caught a pass last season -- a group that was collectively less productive (67 catches, 779 yards, 3 touchdowns) than Mitchell alone (58-865, 5 TDs). Terry Godwin (35-379, 2 TDs) is the lone sure thing here. Otherwise, this position is a gigantic question mark. -- David Ching

20. Oregon Ducks

Quarterback: Who knows? Maybe Dakota Prukop is the second coming of Vernon Adams and the Ducks will be fine at quarterback. For now, though, a healthy level of skepticism is appropriate. When Adams was sidelined last year, the Ducks' other options -- Jeff Lockie and Taylor Alie -- didn't instill any confidence in the coaching staff, which was evident in how the play calling changed. That the Ducks dipped back into the FCS well for another quarterback echoes that sentiment. -- Kyle Bonagura

21. UCLA Bruins

Receiver: UCLA has to replace Jordan Payton (78 catches), Thomas Duarte (53 catches) and Devin Fuller (24 catches), but have few proven options outside of Darren Andrews, who caught 43 passes for 443 yards and a score last season. Andrews is the only returning player who caught more than 11 passes last season, but having Josh Rosen at quarterback should help negate the problem. -- Kyle Bonagura

22. Oklahoma State Cowboys

Offensive line: The offensive line could be the key to the Cowboys' Big 12 title hopes. Mike Gundy's program prioritized the unit in Oklahoma State's recent recruiting class, signing seven offensive linemen, including junior college signee Larry Williams, who could help immediately. If that group can protect quarterback Mason Rudolph while providing holes for Oklahoma State's running game, it would be a major step forward in the Cowboys' title chase. -- Brandon Chatmon

23. Washington Huskies

Receiver: There are a few intriguing pieces (Dante Pettis most notably), but the Huskies will sorely miss leading receiver Jaydon Mickens, who caught 50 passes for 597 yards last year. Tight end Joshua Perkins, who also exhausted his eligibility, was the only other player on the team with more than 30 catches, leaving the Huskies light on proven players. If John Ross, who missed all of last season due to injury, is fully healthy, he presents a true deep threat; Brayden Lenius also showed signs he could develop into a key piece (26 catches, 307 yards last year). -- Kyle Bonagura

24. Florida Gators

Quarterback: The Gators have struggled to find a consistent answer at the game's most important position in recent years. It looked like they might have their quarterback of the present and future in 2015 when Will Grier took the reins, but a suspension and subsequent transfer out of the program have eliminated that possibility. The Gators' options are transfer and walk-on Luke Del Rio, graduate transfer Austin Appleby, true freshmen Feleipe' Franks and Kyle Trask, or Treon Harris, who started games in each of the past two seasons. Only Harris has SEC starting experience, and the offense stagnated late last season when he replaced Grier. Del Rio, who made stops at Alabama and Oregon State, seems to be the popular early favorite, but has only three career games to his credit. -- Sam Khan Jr.

25. Boise State Broncos

Defensive line: The Broncos won't have any returning starters on their defensive line after Kamalei Correa declared for the draft and Tyler Horn and Armand Nance both graduated. After ranking fifth nationally in rush defense (108.2 yards allowed per game), a step back should be expected. Expect some mix of DT Elliot Hoyte, DE Sam McCaskill, DE Jabril Frazier, DE Durrant Miles and DE David Moa to make up the rotation. -- Kyle Bonagura