Tom Dienhart, BTN.com Senior Writer, February 6, 2015

If you can believe it, Duke already has started spring football practice in preparation for the 2015 college football season. The Big Ten won?t break out the pads until March. When it does, the work will begin on replacing some star players.

Earlier, I looked at the five biggest shoes to fill for each Big Ten club – read them all here. We all know players come and go each year, which means these departures below make way for a new wave of names to step up and make their mark. So ahead of the Big Ten's spring football season, here are my 25 biggest shoes to fill overall in 2015.

1. RB Melvin Gordon, Wisconsin. He leaves campus as an all-time great. Gordon ran for 2,587 yards–a Big Ten record and the second-most in FBS history–and 29 TDs in 2014. He earned Big Ten Offensive Player of the Year and Heisman runner-up honors before declaring a year early for the NFL draft. Gordon?s 4,915 career rushing yards rank No. 3 all-time at Wisconsin and No. 6 on the Big Ten all-time list. No one will forget his then-NCAA single-game record 408-yard rushing effort vs. Nebraska in November.

2. OT Brandon Scherff, Iowa. He leaves Iowa City as an all-time great, becoming the fourth Hawkeye to win the Outland Trophy. The All-American was an indomitable force at the key left tackle spot and is projected by most to be a top-10 NFL draft selection.

3. RB Tevin Coleman, Indiana. He left campus a year early as an all-time great. Coleman rushed for a school single-season record 2,036 yards with 15 TDs, averaging 7.5 yards per tote en route to finishing seventh in Heisman voting. No one will forget his 307-yard rushing effort at Rutgers.

4. LB Mike Hull, Penn State. He was the heart-and-soul of a Penn State defense that ranked No. 1 in the Big Ten in scoring (18.6 ppg) and No. 1 in total defense (278.7 ypg). Hull paced the Nittany Lions with 140 tackles, also notching 10.5 TFLs. He was a consensus All-Big Ten choice.

5. WR Tony Lippett, Michigan State. He was voted the Big Ten?s top receiver, a big-play man who stretched defenses. Lippett is the first Spartan to lead the Big Ten in receiving (92.2 ypg.; 1,198 yards) since Charles Rogers in 2002. He also was versatile, as he took reps at cornerback, too.

6. RB Ameer Abdullah, Nebraska. He leaves Lincoln as an all-time great. He put together his third straight 1,000-yard rushing season in 2014, a first in the history of Nebraska program. Abdullah finished 2014 with 1,611 rushing yards, which ranks sixth on the Nebraska single-season list, and he finished his career second all-time at NU with 4,588 career rushing yards. He was a consensus second-team All-Big Ten choice.

7. DE Randy Gregory, Nebraska. Despite missing significant time, Gregory finished with 54 tackles, including a team-high seven sacks for 67 yards in losses, in 2014. Gregory was third on the team with 10 tackles for loss and led the Huskers with 16 quarterback hurries. He was a consensus All-Big Ten pick who declared for the NFL draft.

8. S Kurtis Drummond, Michigan State. He was voted the Big Ten?s defensive back of the year after leading the team in tackles (72), interceptions (4), pass break-ups (11) and passes defended (15).

9. RB David Cobb, Minnesota. He was a franchise player and workhorse who ran 314 times for 1,626 yards-both school single-season records. Cobb?s 2,893 career rushing yards rank seventh all-time in program history. He was consensus second-team All-Big Ten.

10. TE Maxx Williams, Minnesota. He opted to turn pro after playing just two seasons, earning Big Ten Tight End of the Year honors. Williams led team in receptions (36), yards (569), receiving touchdowns (8) and was fourth in yards-per-reception (15.8). His 569 receiving yards and eight receiving touchdowns were a single-season record for a Minnesota tight end.

11. CB Trae Waynes, Michigan State. He was a consensus All-Big Ten selection who opted to turn pro. Waynes was one of the main factors why the Spartans ranked fourth in the FBS in passing-efficiency defense (102.9 rating) and 25th in passing defense (196.0 ypg.). He was a shut-down force.

12. OT Rob Havenstein, Wisconsin. The massive Havenstein leaves a huge void-literally and figuratively-on a strong offensive line. The 6-8, 333-pound Havenstein helped the Badgers rank No. 1 in the Big Ten in rushing (320.1 ypg). He was a consensus first-team All-Big Ten choice.

13. WR Kenny Bell, Nebraska. ?Afro Thunder? completed the most productive receiving career in Nebraska history. He ascended to the top of the school?s career charts for receptions (181) and receiving yards (2,689) in 2014. As a senior, Bell led Nebraska with 47 receptions for a team-high 788 yards and was first-team All-Big Ten by the coaches.

14. LB Jake Ryan, Michigan. He was the heart and soul of a solid Michigan defense who showed grit and toughness in battling back from injury. Ryan?s leadership will be missed, along with production that saw him lead the squad with 112 yards and 14.0 tackles for loss. He was a consensus All-Big Ten choice and leaves having registered a TFL in 30 of his last 40 games. Ryan also tied for second on Michigan?s career forced fumbles list (7) and ranks seventh on the school?s career tackles for loss list (44.5).

15. DT Carl Davis, Iowa. He was a Coke machine in the middle of the line, often creating congestion and stuffing the run. Davis notched 36 tackles with 9.0 TFLs. He was a presence that couldn?t be ignored en route to earning consensus second-team All-Big Ten honors.

16. DT Michael Bennett, Ohio State. A quick, active force in the interior of the line, Bennett was a disrupter. He tallied 41 tackles along with 14 TFL and 7.0 sacks with three forced fumbles. Bennett?s value also extended to his leadership. A class person. He was second-team All-Big Ten by the coaches and media.

17. G Kyle Costigan, Wisconsin. He helped the Badgers rank No. 3 in the Big Ten in offense (468.9 ypg) in 2014, as the attack was spearheaded by the No. 1 rushing game in the conference and was No. 4 in scoring (34.6 ppg). Costigan, one of the toughest players on the team, was a consensus first-team All-Big Ten selection.

18. RB Jeremy Langford, Michigan State. An honorable-mention All-Big Ten choice, Langford ran for 100 yards in a school-record 10 consecutive games. He also eclipsed the 100-yard rushing mark in 16 straight games vs. Big Ten foes en route to running for 1,522 yards in 2014. Langford leaves campus with 2,967 yards rushing and 40 TDs.

19. MLB Damien Wilson, Minnesota. He paced the team with 119 tackles (most tackles by a Gopher since Kim Royston made 123 in 2011) and led the Gophers with 10.5 tackles-for-loss and tied for team lead with 4.0 sack. The former JC transfer was first-team All-Big Ten by the media and second team by the coaches.

20. OT Donovan Smith, Penn State. The massive left tackle had another year of eligibility left but graduated and opted to move on. The program could have used his talent and veteran presence as it looks to build a better front after PSU finished last in the Big Ten in rushing (101.9 ypg). Smith has graduated and opted to turn pro.

21. WR Devin Funchess, Michigan. No, he didn?t have a great year. But Funchess was one of the few playmakers on a largely moribund Wolverines? offense. Funchess led the team with 62 catches for 733 yards and four touchdowns. And then, he turned pro after being second-team All-Big Ten by the coaches. Who will be the go-to wideout in 2015?

22. WR Stefon Diggs, Maryland. He was limited a bit by injury but still was able to earn second-team All-Big Ten honors from the coaches and honorable mention by the media. Diggs led the team in receptions (62), receiving yards (792) and receiving touchdowns (5).

23. QB Gary Nova, Rutgers. He leaves campus as one of the best quarterbacks in school annals. Nova hit 57 percent of his passes for 2,851 yards with 22 touchdowns and 12 interceptions in 2014. His 73 career touchdown passes are the most ever in school annals.

24. RB Akeem Hunt, Purdue. He was one of the most underrated players in the Big Ten, rushing for 949 yards. He also caught a team-high 48 passes for 293 yards. The Boilermakers will miss Hunt?s big-play ability. He also was a hard runner. Who is gonna provide the juice on the offense?

25. CB Doran Grant, Ohio State. A big-time corner, Grant tallied 63 stops, showing aplomb in run support. He also grabbed five interceptions and broke up nine passes. Grant was a first-team All-Big Ten selection by the coaches and second-team by the media.

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About Tom Dienhart BTN.com senior writer Tom Dienhart is a veteran sports journalist who covers Big Ten football and men's basketball for BTN.com and BTN TV. Find him on Twitter and Facebook, read all of his work at btn.com/tomdienhart, and subscribe to his posts via RSS. Also, send questions to his weekly mailbag using the form below and read all of his previous answers in his reader mailbag section.

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