Each week, Sports on Earth is counting down the best returning college football players at every position entering the 2017 season. These rankings are based on a combination of talent, proven production and potential at the college level. They are not NFL Draft rankings. This week, it's the top 25 defensive ends and top 20 defensive tackles.

A Heisman Trophy winner and many other talented offensive players return to college football this season, but in the argument for best overall player in the nation, a case can actually be made for a pair of sophomore defensive tackles in Houston's Ed Oliver and Clemson's Dexter Lawrence. As we continue our preseason player rankings, those rising superstars headline our defensive lineman rankings, split into the top 25 defensive ends and top 20 defensive tackles. Some players play both positions or a hybrid of the two, so they're mostly divided by how they're labeled on depth charts. Either way, consider this a glimpse at the top 45 returning linemen.

2017 Sports on Earth college player rankings: Wide Receivers/Tight Ends | Linebackers | Running Backs

Defensive Ends

25. Justin Lawler, SMU. The Mustangs still ranked 10th in the AAC in yards per play allowed last season, but they made progress by trimming a full yard off their average. Lawler is the player the Mustangs can build around for further progress, a 6-foot-4, 266-pound senior who has started the past two seasons and earned first-team all-conference honors in 2016 with 65 tackles, 15 tackles for loss and six sacks.

24. McTelvin Agim, Arkansas. A prized five-star recruit in the class of 2016, Agim started the final five games of his freshman season, ultimately recording 27 tackles and 5 ½ tackles for loss. The numbers were modest, but Agim should burst into the spotlight as the anchor of new coordinator Paul Rhoads' three-man front. The 289-pound Agim is talented and versatile and a strong bet for a breakout sophomore campaign.

23. Marlon Davidson, Auburn. With Carl Lawson gone, another former blue-chip recruit is waiting in the wings, ready to become a star at defensive end. Davidson had 38 tackles, six tackles for loss and four pass breakups as a true freshman, starting all 13 games.

22. Brian Burns, Florida State. At 6-foot-5, 218 pounds, Burns literally has a lot of room to grow, but as a top recruit, he made an instant impact as a pass-rush specialist, racking up 9 ½ sacks despite having only 24 tackles. Florida State will want him to add bulk and become a more complete player, but he's already a valuable weapon, and he'll be counted on more with DeMarcus Walker gone.

21. Andrew Brown, Virginia. The Mike London era ended poorly, but he did leave behind a few gifts for Bronco Mendenhall, including a pair of five-star recruits from the class of 2014 in safety Quin Blanding and Brown. Both have stuck around for their senior seasons. Brown's potential has been unlocked by the new coaching staff, as he showed flashes of that five-star talent as a junior with 13 tackles for loss and six sacks at defensive end. Expect him to build on that performance to become an All-ACC player.

20. Kylie Fitts, Utah. Fitts had three tackles for loss in last year's opener, only to injure his foot in Week 2 and miss the rest of the season. With top pass rushers Hunter Dimick and Pita Taumoepenu gone, the return of Fitts is huge, as he had seven sacks, four forced fumbles and 10 pass breakups in 2015. A UCLA transfer, Fitts is set to re-emerge as one of the Pac-12's top defenders.

19. Rasheem Green, USC. The 280-pound Green is a versatile player who can line up just about anywhere on coordinator Clancy Pendergast's line. A five-star recruit in 2015, Green became a starter last season and put together a stellar sophomore campaign with a team-high six sacks plus 55 tackles, two forced fumbles and four pass breakups. The strength of the Trojans' defense should be the linebackers, but Green is a valuable asset up front who can also fill space and occupy blockers to free up players like Porter Gustin.

18. K.J. Smith, Baylor. The Bears led the Big 12 in yards per play allowed last season, and Smith stepped up as the leader of a revamped line. He led the team with 12 tackles for loss and seven sacks as a junior, finishing the season with 67 tackles and earning first-team All-Big 12 honors. Coach Matt Rhule and coordinator Phil Snow built excellent defenses at Temple, and Smith and linebacker Taylor Young will be counted on as the senior cornerstones of the new staff's first Baylor defense.

17. Cece Jefferson, Florida. In 2015, Jefferson was one of the nation's top recruits, ranking No. 7 overall in the 247Sports composite rankings. Now, the Gators are counting on Jefferson to live up to that billing as they rebuild their defense with so much talent gone to the NFL in the past two drafts. A part-time starter the past two seasons, Jefferson has 59 career tackles and 15 career tackles for loss. Jefferson is a versatile player who can slide inside and play some tackle, and the hope is for a breakout season rushing the passer to help prevent too much of a drop-off for the team on defense.

16. Hercules Mata'afa, Washington State. Mike Leach's offensive players are always much more likely to make lists like this, but the Wazzu defense has made strides under coordinator Alex Grinch. The unit has a star in Mata'afa, a second-team All-Pac-12 pick who finished his sophomore season with 47 tackles and 13 ½ tackles for loss. The relentless, speedy Mata'afa sets the tone for a defense that should become more disruptive in 2017.

15. Jaylon Ferguson, Louisiana Tech. Conference USA had only one player with double-digit sacks last season, and that was Ferguson, whose 14 ½ tied him for third nationally. The 6-foot-5, 255-pound junior has 20 ½ sacks in two seasons, and he's coming off a phenomenal sophomore campaign -- his first as a full-time starter -- in which he also had 49 tackles and four forced fumbles. Ferguson is one of the Group of Five's top defenders and one of the best pass rushers nationally, period.

14. James Looney, California. Looney, who transferred from Wake Forest early in his career, will slide from tackle to end as a senior in the 3-4 defense favored by new coach Justin Wilcox and coordinator Tim DeRuyter. At 6-foot-3, 280-pounds, the versatile Looney is well-suited for the role. In two years at Cal, Looney has a total of 89 tackles with 23 starts, developing into a needed impact player for a defense that has, to put it mildly, been unable to get stops. But don't let Cal's lackluster defensive results fool you: Looney is the real deal, the player also responsible for finishing off the Golden Bears' game-winning goal-line stand against Utah.

13. Ja'Von Rolland-Jones, Arkansas State. The overall player of the year in the Sun Belt last season, Rolland-Jones was a dominant player off the edge, racking up 57 tackles, 21 tackles for loss and 13 sacks. The 244-pounder Rolland-Jones enters his senior year with 44 career tackles for loss, as he's been in the top 10 in the Sun Belt three years in a row in that category.

12. Josh Sweat, Florida State. It's Sweat's turn to shine now. Star end DeMarcus Walker is gone, leaving Sweat as the standout at end, along with another emerging star in sophomore Brian Burns. A top-10 recruit in the class of 2015, Sweat had to rebound from a serious knee injury as a senior in high school. He's been inconsistent in his first two years at Florida State, but he's shown big-time flashes, ultimately finishing last season with 41 tackles and seven sacks. Sweat had 1 ½ sacks in each of the final three games of 2016, and he should team with Burns to form one of the nation's top end duos despite the departure of Walker.

11. Dorance Armstrong, Kansas. The Jayhawks' defense finished ninth in the Big 12 in yards per play allowed, but the unit has made progress and has a chance to be solid this season, thanks especially to the defensive line. Armstrong, a 246-pound junior, broke out in 2016 with 56 tackles, 20 tackles for loss, 10 sacks and three forced fumbles to earn first-team All-Big 12 honors. He's quickly become one of the nation's most dangerous players off the edge thanks to his burst and speed.

10. Da'Shawn Hand, Alabama. Heralded as the No. 1 overall recruit in the class of 2014 by Rivals.com -- ahead of Myles Garrett, Jabrill Peppers, Leonard Fournette, Deshaun Watson and numerous proven stars -- Hand has had to wait his turn as part of the incredibly deep and talented Alabama defensive line. Now, with Jonathan Allen and Dalvin Tomlinson gone, it's finally time for Hand to step into a full-time starting role. It's a strange trajectory; anywhere else, he would have been expected to play right away, given his five-star billing. At Alabama, he had 21 tackles and 3 ½ tackles for loss as a junior. But with the turnover in the Crimson Tide's front seven, the time is now for Hand to emerge.

9. Duke Ejiofor, Wake Forest. The Demon Deacons are coming off their first bowl season since 2011, and while that relative success, driven by the defense, led to defensive coordinator Mike Elko being lured away by Notre Dame, the unit's best player, Ejiofor, rejected the NFL to return for his senior season in Winston-Salem. The 6-foot-4, 270-pound Ejiofor is a havoc-creating force at defensive end, coming off a season in which he had 10 ½ sacks, four pass breakups, two forced fumbles and an interception.

8. Sam Hubbard, Ohio State; 7. Tyquan Lewis, Ohio State; and 6. Nick Bosa, Ohio State. Bosa has the known name, Lewis is the reigning Big Ten defensive lineman of the year and Hubbard has a chance to be as good as either of them. Such is the wealth of talent available on the Ohio State defensive line, particularly at end. Hubbard actually had a somewhat quiet sophomore season -- eight tackles for loss, 3 ½ sacks -- that didn't really improve upon the potential he showed as a freshman, but make no mistake, his ceiling is seemingly unlimited. The 6-foot-5, 265-pound junior played safety in high school and has tremendous versatility and athleticism. Lewis is the seasoned veteran, the productive senior who had a team-high 10 ½ tackles for loss and eight sacks as a junior, also forcing three fumbles and breaking up two passes. Bosa went to Columbus with impossible shoes to fill, but he welcomed the comparisons to his brother Joey -- last year's NFL defensive rookie of the year -- by even wearing the No. 97 jersey. Joey was a 6-foot-5, 278-pound five-star recruit who had 13 ½ tackles for loss as a freshman. Nick was a 6-foot-4, 270-pound five-star recruit who had five sacks as a freshman. The comparisons are impossible to avoid, but the younger Bosa has a ceiling as great as his brother's and is set to make a name for himself on his own as a potential All-American. Rank these three in whichever order you please. They all have All-America ability … and the fourth end, Jalyn Holmes, isn't far off either.

5. Rashan Gary, Michigan. The No. 1 overall recruit in the class of 2016, Gary saw time in a rotational role as a true freshman. What was a crowded defensive line makes way for Jim Harbaugh's recruits now, and Gary will be thrust into a sizable role in which he's expected to become a star. The 6-foot-5, 287-pound Gary was a versatile monster in high school, and his rookie season -- with 27 tackles and five tackles for loss -- showed a player merely scratching the surface. With a larger role as a sophomore starter, expect Gary to become an All-Big Ten performer, and likely more.

4. Marquis Haynes, Ole Miss. A prolific player off the edge, Haynes is only 225 pounds, but he fits the Rebels' lean, fast and aggressive defense. While the unit took a huge step back last season, Haynes continues to be a productive playmaker, with 24 1/2 career sacks after he had 53 tackles, seven sacks, three forced fumbles and an interception as a junior. While undersized, Haynes is a terrific athlete whose quickness is tough for most college tackles to consistently contain.

3. Clelin Ferrell, Clemson. The Tigers continue to crank out star-studded defensive lines under coordinator Brent Venables, and while the tackles are the biggest names on the 2017 line, Ferrell proved late in the 2016 season that he's capable of being in the All-America discussion, too. After redshirting, the 6-foot-5, 265-pound Ferrell started all 15 games for the national champions, finishing the season with 44 tackles, 12 ½ tackles for loss, six sacks and two pass breakups. Six of those tackles for loss came in the final the ACC title game and the two playoff contests. Ferrell's job is made easier by the attention devoted elsewhere on the line, but his skill set demands attention, too, and he was only just scratching the surface in his first year of action last year.

2. Bradley Chubb, N.C. State. The Wolfpack line has been underappreciated nationally, but that's likely to change as Chubb emerges as a star. Chubb broke into the starting lineup as a sophomore in 2015 and became a second-team All-ACC player last season, racking up 21 ½ tackles for loss, 10 sacks, 57 tackles and three forced fumbles to lead a disruptive defense that was particularly strong against the run. The 275-pound senior is a well-rounded player who is the leader of what can be one of the nation's top defensive lines.

1. Harold Landry, Boston College. Even with coordinator Don Brown gone, the Eagles continued to field a stellar defense last season. Nobody was more responsible for the defense's performance than Landry, a talented edge rusher who could have turned pro but decided to return for his senior season and take aim at All-America honors for the second year in a row. As a junior, the 250-pound Landry led the nation with 16 ½ sacks and seven forced fumbles, along with racking up 51 tackles and four pass breakups, plus an interception. He has first-round NFL edge rusher written all over him.

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Defensive Tackles

20. Justin Jones, N.C. State. The Wolfpack have a rock-solid defensive line led by Bradley Chubb at end, with a stellar tackle tandem featuring Jones and fellow senior B.J. Hill. Either Jones or Hill could be listed here, but we'll highlight the 300-pound Jones, who had 43 tackles and 6 ½ tackles for loss last season for a defense that was often fantastic against the run and should be even better this season.

19. Poona Ford, Texas. The Longhorns defense was a disappointment last year, but new coordinator Todd Orlando inherits plenty of talent, with the front in particular bursting with potential. Ford drew rave reviews from coach Tom Herman in spring practice -- "fanatical, championship effort" -- and the 5-foot-11, 303-pound senior is coming off a season in which he finished fourth on the team with 54 tackles.

18. Daniel Wise, Kansas. In addition to boasting a first-team All-Big 12 end in Dorance Armstrong, the Jayhawks have an honorable mention choice at tackle who's likely to become a first- or second-teamer as a junior. Wise had 38 tackles and 10 tackles for loss last season -- including three tackles for loss to help spur the win over Texas. The 290-pound Wise also has three career blocked kicks, proving to be a disruptive penetrator on the interior.

17. Will Geary, Kansas State. Geary sat out spring practice for personal reasons, but the hope is that the senior tackle is ready to go for the season. A first-team All-Big 12 pick in 2015, Geary was overshadowed by star end Jordan Willis last year, but with Willis gone, Geary and end Reggie Walker are expected to be the leaders of this defensive front. The 298-pound Geary is a former walk-on with 30 starts and 16 career tackles for loss under his belt.

16. Kendrick Norton, Miami; and 15. R.J. McIntosh, Miami. It's hard to choose one over the other. The Hurricanes are bursting with rising stars in their front seven, and McIntosh and Norton have become an excellent junior tandem. The 293-pound McIntosh had 47 tackles, 9 ½ tackles for loss and two pass breakups last season. The 312-pound Norton had 39 tackles and 10 tackles for loss and got a third-team All-ACC nod. They're key cogs in what should be a terrific run defense.

14. Dre'Mont Jones, Ohio State. Ohio State is absurdly deep at defensive end, which will certainly be a stronger position than tackle, but the Buckeyes are, not surprisingly, still in good shape on the interior. The leader is Jones, a four-star recruit who emerged as an impact player as a redshirt freshman, replacing the injured Terry Sprinkle early in the season and ultimately finishing with 52 tackles and four tackles for loss. Sprinkle is back, but Jones has one of the two starting spots locked down and shouldn't be overlooked as a rising star amid all the deserved attention devoted to the ends.

13. David Moa, Boise State. Recruited as a defensive end, Moa has become a force as an undersized nose tackle, listed at just 262 pounds. As a sophomore, he was a first-team All-Mountain West selection, racking up 8 ½ sacks and four pass breakups. Moa shifted away from the nose in the spring, but wherever he plays, he's a relentless player who will be the star of a Broncos defense that returns just four starters.  

12. Greg Gaines, Washington. The 321-pound Gaines became a full-time starter as a sophomore in 2016, finishing with eight tackles for loss as an emerging force along a big, disruptive defensive front. Gaines and Vita Vea give the Huskies a pair of All-Pac-12-caliber 300-pounders on their line. Gaines is a physical force against the run in particular.

11. Steven Richardson, Minnesota. The Golden Gophers had a strong run defense and finished 14th in yards per play allowed last season, and perhaps nobody was more responsible for that performance than Richardson. A 6-foot, 300-pound senior, Richardson has started 32 games over the past three seasons, and now he's one of the Big Ten's top returning defensive players, the centerpiece of what will be a new-look defense after he had a team-high 11 tackles for loss in 2016.

10. Harrison Phillips, Stanford. Injuries limited Phillips' growth earlier in his career -- he missed nearly all of the 2015 season -- but now he's expected to be the centerpiece of the Cardinal defensive line with Solomon Thomas gone to the NFL. The 285-pound Phillips emerged as a standout last season, with 46 tackles and 9 ½ tackles for loss. Phillips is tough and quick in the middle of the Cardinal line, a stellar player against the run who can also make plays as a pass rusher.

9. Lowell Lotulelei, Utah. The younger brother of form Utes standout Star Lotulelei continues to excel on the interior of the Utes' defense. The 310-pound senior actually went from first-team All-Pac-12 as a sophomore to honorable mention as a junior, but while he's never had huge numbers -- 28 tackles, 8 ½ tackles for loss last year -- he's been a force for Utah since his freshman year, providing the Utes with a big, physical presence to help the ends create havoc off the edge.

8. Maurice Hurst, Michigan. Hurst has started only four times in 33 career games, but he's already made a name for himself and now will get elevated into a larger role as Michigan says goodbye to Ryan Glasgow, Chris Wormley and others up front. The defensive line is still in great hands with players like Rashan Gary and Hurst, a 282-pound senior who had 11 ½ tackles for loss last season for an excellent Wolverines defense.

7. Derrick Nnadi, Florida State. With DeMarcus Walker gone, Nnadi is now the clear seasoned leader of an impressive FSU defensive line. The powerful 312-pound tackle decided to return for his senior year after a junior season in which he bounced back from early ankle troubles to record 49 tackles and 10 ½ tackles for loss. Stout against the run and also able to contribute as a pass rusher, Nnadi grew into a first-team All-ACC pick and can duplicate that performance in 2017.

6. Vita Vea, Washington. The Huskies defense has become a machine, churning out NFL-quality talent with an ability to reload. This year, the pressure is on the defensive front to ease the transition of a new-look secondary. That will be easier with players like Vea, the 6-foot-4, 346-pound behemoth in the middle who started only five games last year but was named second-team All-Pac-12 anyway, recording 39 tackles and sacks. With Elijah Qualls gone, Vea becomes even more important as he anchors what can be one of the nation's top front sevens.

5. Trenton Thompson, Georgia. Thompson withdrew from classes in the spring while dealing with a shoulder injury, but he's expected to recover and rejoin the team, where he's a key cog -- perhaps with the highest upside -- for a defense that has a chance to become exceptional in Kirby Smart's second season as coach. Thompson was rated the No. 1 overall recruit in the class of 2015, and the 295-pound junior is growing into the star he was hoped to be, after finishing third on the team with 56 tackles and first with 9 ½ tackles for loss and five sacks -- three of which came in a dominant Liberty Bowl performance.

4. Da'Ron Payne, Alabama. Yet another five-star Alabama defensive line recruit blossoming into a superstar. The 319-pound Payne flashed big-time potential as a rotational backup in his freshman season, then became a key part of a dominant defense as a starter last season. The stats don't necessarily show it -- 36 tackles, 3 ½ tackles for loss -- but Payne's job is to occupy the middle at nose guard, a role he filled admirably for a defense that allowed a paltry two yards per rush attempt. The Crimson Tide have to deal with a lot of turnover in their front seven, but Payne anchors a new-look unit that will still be as good as any in the country.

3. Christian Wilkins, Clemson. Wilkins does anything Clemson needs him to do, whether it's catching a deep pass from a punter on fourth down in a playoff game, acting as a receiver and blocker in the red zone or, more conventionally, lining up at either end or tackle on the defensive line. As a freshman tackle, Wilkins had 33 tackles. As a sophomore end, Wilkins had 48 tackles and 13 tackles for loss. Now, the charismatic 310-pound junior is expected to shift back inside with Carlos Watkins gone, teaming with Dexter Lawrence to form a dominant interior tandem.

2. Dexter Lawrence, Clemson. Already being floated as the potential No. 1 overall pick in the 2019 NFL Draft, Lawrence instantly looked like an NFL player for the Tigers, becoming arguably the best player on a star-studded defensive line as a true freshman. The 6-foot-5, 345-pound Lawrence is much more than a space eater, as he finished the year with 62 tackles and 6 ½ sacks. He can overwhelm opponents with his size, and he can overwhelm them with his freakish athleticism and quickness.

1. Ed Oliver, Houston. Oliver became the rare five-star recruit who signed with a Group of Five program, and he instantly delivered on the hype and high expectations. Oliver had two tackles for loss in the Cougars' opening win over Oklahoma, and he went on to an All-America debut season in which he finished with 66 tackles, 22 ½ tackles for loss, five sacks, nine pass breakups and three forced fumbles. The 290-pound Oliver is a pro-ready machine, versatile enough to line up anywhere on the defensive line and disrupt everything an opposing offense does. Group of Five players are almost never mentioned in the conversation for best player in the country at any position, but Oliver has an argument.

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