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. The first part covered wide receivers and tight ends. This week, it's linebackers.

Four of the five finalists for last year's Butkus Award, including winner Reuben Foster, are off to the NFL, but there is a deep crop of talented linebackers returning in the 2017 college football season to make this a competitive list in which players might be a bit harder to place than some of the other positions. We're including all linebackers together, whether they're 3-4 edge rushers, 4-3 middle linebackers or anything else that has them labeled "linebacker" on their team's roster. Here are the top 35 entering the 2017 season.

35. Darrin Kirkland, Tennessee. The underrated Kirkland was missed for a chunk of last season, as he was lost for five games with an ankle injury. He still had 45 tackles and five tackles for loss, and as a junior at middle linebacker, a healthy Kirkland can become perhaps the best player on a Tennessee defense that loses stalwarts Derek Barnett, Cam Sutton and Jalen Reeves-Maybin.

34. Nyles Morgan, Notre Dame. The Fighting Irish defense was a mess for most of last season, leading to the in-season firing of coordinator Brian VanGorder. Morgan showed potential, though, and he should thrive under new coordinator Mike Elko. Morgan, who has slimmed down to 238 points, emerged as an impact player in 2016 with Jaylon Smith gone, finishing with 90 tackles and six tackles for loss.

33. Taylor Young, Baylor . While only 5-foot-9, 225 pounds, Young has put up 265 tackles in his career as a three-year starter. Injuries have been an issue -- he missed three games last season and sat out spring practice -- but Young is a hard-hitting athlete poised to play a vital role in a new-look defense under coach Matt Rhule.

32. Andrew Motuapuaka, Virginia Tech. Motuapuaka continues to make a bigger and bigger impact each season with 241 career tackles, including 114 at middle linebacker for the Hokies as a junior last season. He also had 5 1/2 tackles for loss, four pass breakups and three interceptions, earning second-team All-ACC honors for a defense that jumped back up from 61st to 19th in yards per play allowed in an ACC Coastal-winning season.

31. Ty Summers, TCU. The Horned Frogs defense has hit some rough patches, but there's no doubt that Gary Patterson has talent to build around at linebacker thanks to the duo of Travin Howard, a first-team All-Big 12 performer, and Summers, a second-team choice. The 235-pound junior has been a machine in two seasons, already with 207 career tackles. He even had 23 in one game against Baylor in 2015.

30. Jahlani Tavai, Hawaii. Even in a bowl season, Hawaii's defense had a rough year, but don't blame Tavai. As a sophomore, the 6-foot-4, 235-pound Tavai earned first-team All-Mountain West honors after a prolific season in the middle of the Warriors defense in which he racked up 129 tackles, 19 ½ tackles for loss and an interception. He had 9 ½ tackles for loss in the last four games alone.

29. T.J. Edwards, Wisconsin. The Badgers' edge rushers have received the attention and accolades the past couple years, but Edwards has been a stalwart on the inside, leading the team in tackles each of his first two years. With Jack Cichy missing the second half of the season, Edwards had 89 tackles, 8 ½ tackles for loss and three interceptions as a sophomore, proving to be an integral part of a top-10 run defense nationally.

28. Kenny Young, UCLA. Lost in all the attention devoted to UCLA's offensive meltdown was the fact that the defense ranked 15th in yards per play allowed. A second-team all-conference pick, Young finished second on the team with 90 tackles, and he also had five sacks and an interception. Defensive coordinator Tom Bradley has a reputation for churning out quality linebackers, as have the Bruins in recent years. Young is the next standout.

27. Mike McCray, Michigan. There are familiar names on the Michigan defense, but only one who was actually a starter last year. That's McCray, the senior linebacker on a unit that is experiencing a changing of the guard with a ton of seniors off to the NFL. The 6-foot-4, 248-pound McCray finished second on the team with 75 tackles, and he had 13 tackles for loss, two interceptions and six pass breakups as a productive weapon in new coordinator Don Brown's defense, all after missing the 2015 season with a shoulder injury.

26. Troy Dye, Oregon. There was so much bad news attached to the Oregon defense last season that Dye didn't get enough credit for his fantastic freshman season as he stood out as easily the biggest bright spot on the unit. Rated a three-star safety recruit, Dye bulked up to 225 pounds and emerged as the Ducks' leading tackler with 91. He had 13 tackles for loss -- including 4 ½ in his debut -- and an interception, and he'll at least give new defensive coordinator Jim Leavitt a clear budding star to build around as he shifts inside in their 3-4 defense.

25. Matthew Thomas, Florida State. At long last, Thomas began living up to the potential last season. After injuries and ineligibility limited the five-star recruit for three years, he started 12 games in 2016 and led the Seminoles with 77 tackles and made 11 tackles for loss. The 6-foot-3, 227-pound Thomas returned for a fifth year after a particularly strong finish to last season, including 15 tackles and 3 ½ tackles for loss in the Orange Bowl win over Michigan. Thomas teaming with Ro'Derrick Hoskins makes linebacker a position of strength for the Noles after a few years of struggles.

24. Shaquem Griffin, UCF. Griffin's left hand was amputated at age 4, but that hasn't stopped him from becoming a football star, including AAC defensive player of the year honors as a junior. The 6-foot-1, 213-pound senior was a consistent playmaker last season for a much-improved UCF squad, finishing with 92 tackles, 20 tackles for loss, seven pass breakups and an interception.

23. Stacy Thomas, Louisville. Perhaps overshadowed by Devonte Fields and Keith Kelsey in what was an excellent linebacking corps, Thomas steps to the forefront of the unit as a senior. In his first year in the starting lineup, Thomas finished second on the team with 85 tackles and had 7 ½ tackles for loss and an interception. The 240-pound Thomas is a physical player who can fight through traffic.

22. Shaquille Quarterman, Miami. Improbably, Miami's defense improved from 86th to ninth in yards per play allowed despite starting three freshmen at linebacker: Quarterman, Michael Pinckney and Zach McCloud. All three showed promise, but the 240-pound Quarterman headlines the unit, having racked up 84 tackles, 10 tackles for loss and a fumble return touchdown -- enough to earn third third-team All-ACC honors.

21. Keishawn Bierria, Washington. While he hasn't received quite as much publicity as fellow senior Azeem Victor in the middle of the Huskies' defense, that could change. Bierria is a second-team All-Pac-12 pick, an athletic 230-pound linebacker who had 70 tackles, five tackles for loss and two forced fumbles, growing into an important force to make this as impressive of a linebacking duo as any in the country.

20. Jack Cichy, Wisconsin. Cichy starred for an excellent Badgers defense the first half of last season before a torn pectoral knocked him out. In the first seven games, Cichy racked up 60 tackles, seven tackles for loss -- 3 ½ against Ohio State -- and two forced fumbles, with double-digit tackles in each of his last three games. With T.J. Watt and Vince Biegel moving on, Cichy returns to headline what should still be an excellent linebacking unit leading another strong run defense.

19. Jason Cabinda, Penn State. Early last season, Penn State's linebacking corps was ravaged by injuries, and that included Cabinda's five-game absence from the middle. His return was a massive boost and proved to be a big reason for the Nittany Lions' season-changing win over Ohio State, as he returned that night to rack up 13 tackles and a pivotal sack on the Buckeyes' second-to-last play. Cabinda ended up with 81 tackles in nine games, proving again to be a key leader and steady force for the Penn State defense.

18. Skai Moore, South Carolina. Moore led the Gamecocks in tackles as a freshman way back in 2013. He did it again in '14, and again in '15, peaking with 111 tackles in that impressive junior season in which he was a second-team All-SEC pick. Unfortunately, last season Moore was sidelined the whole way because of herniated disk surgery in the offseason. Now, Moore is back as the centerpiece of the defense in Will Muschamp's second season.

17. Roquan Smith, Georgia. After playing as a true freshman backup, the speedy Smith broke into the starting lineup as a sophomore and emerged as the leading tackler in the new-look defense under coach Kirby Smart. Smith had 95 tackles -- 36 more than anybody else on the team -- with five tackles for loss and two forced fumbles. Smith missed the spring with an injury, but he's become a leader in the middle of the defense, headlining a talented linebacking corps that could spur a breakthrough season for this defense.

16. Rashaan Evans, Alabama. Evans didn't start a game until the playoff against Washington when teammate Shaun Dion Hamilton was injured, but the senior has waited his turn and made a noticeable impact when given a chance as a rotational player. Formerly an outside linebacker, Evans moved inside last season and finished eighth on the team with 53 tackles, also recording four sacks. He's an explosive, versatile talent primed for a breakout when given a bigger role with Reuben Foster gone.

15. Kendall Joseph, Clemson. The Tigers defense has been bursting with so much talent that it can be difficult for every deserving player to get enough credit. Joseph was nowhere to be found on the All-ACC teams last year despite finishing with 108 tackles, 12 ½ tackles for loss and an interception -- numbers nearly equal to the much more widely known Ben Boulware. Boulware is gone, and it's Joseph's time for the spotlight in leading this linebacking corps. Their job is all made easier by the absurd talent Clemson has on the line, but Joseph is a rising star poised to garner increased attention as a junior.

14. Ogbonnia Okoronkwo, Oklahoma. With Eric Striker gone, a lot of pressure was placed on Okoronkwo to fill those shoes. Doing that would be too much to ask, but Okoronkwo had a stellar starting debut, stepping up with a team-high nine sacks (nobody else had more than 2 ½) and 71 tackles. Okoronkwo plays essentially a hybrid end/linebacker spot in which his primary responsibility is creating havoc off the edge and getting to the quarterback.

13. Travin Howard, TCU. The Horned Frogs favor versatility over size in their 4-2-5 defense, and Howard -- a 6-foot-1, 213-pound former safety -- has fit in perfectly as a linebacker alongside Ty Summers. Only three players nationally had more than Howard's 130 tackles last season (Summers was right behind at 121). He averaged 10 per game, with three tackles for loss and an interception. As a senior, the first-team All-Big 12 pick will be counted on to help elevate the level of play on this defense after the unit overall had a disappointing 2016 season.

12. Jerome Baker, Ohio State. Baker broke into the starting lineup last season after Dante Booker suffered an early injury, and he took advantage of the opportunity. Baker had a pick-six in the win at Oklahoma and finished the year with 83 tackles, 9 ½ tackles for loss and two interceptions, emerging as yet another standout player on a typically loaded Buckeyes. Raekwon McMillan is gone, but Ohio State will still have an excellent linebacking corps with the speedy junior Baker teaming with Chris Worley and a healthy Booker.

11. Porter Gustin, USC. A rising star off the edge, Gustin broke into the starting lineup full time last year, racking up 68 tackles, 13 tackles for loss and four pass breakups. The 6-foot-5, 260-pound junior is built like a defensive end and typically lines up in a stand-up rush end position, using explosiveness and tenacity off the edge to collapse the pocket and blow up plays in the backfield.

10. Shaun Dion Hamilton, Alabama. Alabama's supply of star linebackers never runs out. The Crimson Tide missed Hamilton alongside Reuben Foster in the playoff, as he tore his ACL in the SEC championship game. Despite the injury, Hamilton is expected to be ready for his senior season, when he'll step into an even more important role as the leader at the center of the defense with Foster gone. The 6-foot, 232-pound Hamilton is a smart, crafty linebacker who had 64 tackles, nine tackles for loss and two picks before the injury.

9. Tegray Scales, Indiana. The Hoosiers' defense experienced a massive turnaround last year under coordinator (and now head coach) Tom Allen. No player was more valuable than Scales. The 227-pound Scales broke out as a junior and led the nation with 23 ½ tackles for loss. He had 126 tackles, a pick-six, a forced fumble and seven sacks, wreaking havoc on opposing offenses.

8. Jordan Jones, Kentucky. Coach Mark Stoops has made a point of heavily recruiting the state of Ohio, and Jones has been one of the key finds from the state, out of Youngstown's Cardinal Mooney. The 6-foot-2, 221-pound junior emerged as a star last season, providing a needed disruptive boost to the Wildcats defense with 15 ½ tackles for loss, 109 tackles and four pass breakups. Named second-team All-SEC by the conference's coaches, Jones is a high-energy player with impressive closing burst.

7. Azeem Victor, Washington. Victor broke his leg on Nov. 12 in the loss to USC, causing him to miss the Huskies' final four games. Before then, he earned first-team All-Pac-12 honors with his impressive play in the middle of the Huskies' defense. His numbers -- 67 tackles, three tackles for loss, a forced fumble -- weren't overwhelming, but the 6-foot-4, 232-pound senior is an instinctive, athletic and well-rounded player whose return will be a huge boost to a defense that has a lot of turnover on the back end.

6. Tremaine Edmunds, Virginia Tech. A matchup nightmare for opponents, Edmunds is a perfect fit for defensive coordinator Bud Foster, who can use the 6-foot-5, 236-pound junior linebacker to move around the formation and attack opposing backfields in a variety of ways. After playing sparingly as a freshman, Edmunds broke out last year as a second-team All-ACC selection, finishing with 106 tackles, 18 ½ tackles for loss, three pass breakups and an interception. He's a disruptive, explosive athlete, primed to become an All-American.

5. Cameron Smith, USC. Smith burst onto the scene with three interceptions in one game against Utah as a freshman in 2015, only to miss the final four games of that season with a knee injury. Smith recovered and returned to form as a sophomore, growing into a steady star for the Trojans defense, as he was a second-team All-Pac-12 choice with 83 tackles, seven tackles for loss and four pass breakups, showing off an instinctive game in which he's rarely out of position.

4. Malik Jefferson, Texas. The No. 1 linebacker in the recruiting class of 2015, Jefferson made an immediate impact for Charlie Strong's defense, starting nine games and finishing with 61 tackles and seven tackles for loss. Hyped as a potential All-American last year, he didn't quite make the expected leap forward in Year 2. His numbers were similar -- nine starts, 62 tackles, 8 ½ tackles for loss -- but his play was up and down, just like the rest of the Texas defense, and he even dealt with a benching. Still, there's no doubting Jefferson's potential. He's a fantastic athlete, and he has the talent to reach that high ceiling under new coordinator Todd Orlando as he shifts back to outside linebacker.

3. Josey Jewell, Iowa. The only one of five 2016 Butkus Award finalists to not play in the SEC -- and the only one back in 2017 -- Jewell has racked up 250 tackles over the past two seasons. Named a captain as a sophomore, Jewell has put together a prolific career in which he's a proven run stopper but also is an asset in coverage, including nine pass breakups last season and four interceptions in 2015.

2. Micah Kiser, Virginia. Bronco Mendenhall faced a steep rebuilding job when he accepted the Virginia job, but things were made a bit easier on defense by the presence of a player like Kiser in the middle. In 12 games, Kiser led all Power Five players with 134 tackles as a junior, reaching double digits in eight games. He also had 10 tackles for loss, seven pass breakups, five forced fumbles and an interception, proving to be a multi-dimensional talent adept in coverage on top of being disruptive and reliable against the run, with impressive range.

1. Arden Key, LSU. The long and athletic edge rusher missed spring ball while taking a personal leave of absence from the team, but he is expected to return for this season. An explosive athlete, Key was listed at only 238 pounds last season and played a hybrid end/outside linebacker role in new defensive coordinator Dave Aranda's defense. He finished his sophomore year with 56 tackles, 12 sacks, three forced fumbles and three pass breakups, and while he needs to develop into a more physical player, there is no more disruptive player off the edge because of his speed. He's the type of weapon that an offense has to be aware of at all times, and even then his athleticism can be too much to handle.

* * *
Contact Matt at matt.brown5082@gmail.com and follow him on Twitter @MattBrownCFB and Facebook.