With spring ball a month away, we've been ranking position groups in the Big 12. These evaluations have been based on past performance, future potential and quality depth. We continue the series with defensive line:

1. Baylor: The Bears boast two bona fide All-American candidates up front in tackle Andrew Billings and end Shawn Oakman, who put off the draft to return for his senior season. Both are coming off first-team All-Big 12 seasons. Alongside Billings, Beau Blackshear will be a three-year starter. The group has the potential to be scary good -- and also just plain scary.

2. TCU: The Horned Frogs lose three-time All-Big 12 lynchpin Chucky Hunter; the rest of the D-line, however, is back. Fellow tackle Davion Pierson will finally be out of Hunter's shadow. He quietly was one of TCU's better players last year. The entire playmaking defensive end quartet of Josh Carraway, Mike Tuaua, James McFarland and Terrell Lathan is back, as well. If junior Tevin Lawson or sophomore Chris Bradley can fill Hunter's production, this unit has a chance to be as good as it was in 2014 -- if not better.

3. Texas: Malcom Brown deservedly received all the attention for his magnificent 2014 campaign. But he also overshadowed Hassan Ridgeway, who was one of the Big 12's better tackles by the end of the season. Ridgeway is a breakout bet for 2015. He'll be flanked by Desmond Jackson, who is coming back from season-ending foot injury, and former ESPN 300 signee Poona Ford. At end, the Longhorns lose Cedric Reed, but have Naashon Hughes, Caleb Bluiett and Shiro Davis back as well as Derick Roberson, the team's top overall signee in 2014. ESPN JC50 DE Quincy Vasser rounds out a deep and talented rotation.

4. Oklahoma State: Emmanuel Ogbah is the reigning Big 12 Defensive Lineman of the year, and will only be a junior. Last season in his first as a starter, he finished second in the league with 11 sacks and third with 17 tackles for loss. Jimmy Bean is a two-year starter at the other end. James Castleman and Ofa Hautau are gone inside, but Oklahoma State has ESPN JC 50 recruit Motekiai Maile and several up-and-coming options at tackle, including Vincent Taylor, Vili Leveni and four-star signee Darrion Daniels.

5. Oklahoma: The Sooners had a disappointing 2014, due in part to a defensive line that failed to dominate as expected. Yet despite losing Jordan Phillips, Chuka Ndulue and Geneo Grissom, Oklahoma is hardly devoid of talent up front. Charles Tapper is one year removed from a first-team All-Big 12 season. The Sooners need him to return to his disruptive 2013 level. The program is excited about Matt Dimon, Matthew Romar, Charles Walker and D.J. Ward after they served bit roles last season. The biggest question is nose tackle, where Phillips' departure leaves a huge void in Mike Stoops' 3-4 scheme. Jordan Wade is the only returning 300-pound defender on the roster, but he fell out of the rotation last year. ESPN 300 signee Neville Gallimore could be the long-term answer there, but it's unknown how ready he'll be able to assist as a true freshman. The Sooners also have to replace prolific D-line coach Jerry Montgomery, who recently left for the Green Bay Packers.

6. Kansas State: Travis Britz is one of the top returning tackles in the league, and should be healthy after missing K-State's final three games with an ankle injury. Jordan Willis was active at end with four sacks. Veteran backup Marquel Bryant likely will step in for Ryan Mueller opposite Willis. Rotation tackles Will Geary and Demonte Hood will be asked to play bigger roles in 2015. It will be interesting to see if defensive tackle Bryce English, the top signee in K-State's 2015 class, or defensive tackle Trey Dishon, perhaps the sleeper of the class, will be able to help early on, as well.

7. West Virginia: Shaq Riddick was West Virginia's only real pass-rush threat last season, and he's gone. Still, the team can count Kyle Rose, Noble Nwachukwu and Christian Brown -- all experienced players. The Mountaineers need one of their two incoming juco ends, Larry Jefferson or Xavier Pegues, to supply the pressure Riddick brought off the edge.

8. Texas Tech: The Red Raiders finally have a chance to hold their own. Pete Robertson is a big reason why, having led the Big 12 with 13 sacks last year. Branden Jackson is a two-year starter on the other side of the line and a solid player. To combat what was a disastrous run defense in 2014, Tech is hopeful that former juco transfers Rika Levi and Keland McElrath will be more effective in their second seasons. The "X" factor will be incoming freshman Breiden Fehoko, who was the No. 51 overall recruit in the country. If Fehoko can give the Red Raiders something early, they will instantly be better.

9. Kansas: The Jayhawks have the fewest returning starters in the Big 12, but they do bring back two-year starter Ben Goodman. Andrew Bolton is Kansas' top returner on the inside. Juco transfer Jacky Dezir should add depth in the middle. Incoming freshman end Dorance Armstrong has the potential to be a difference-maker in time.

10. Iowa State: The Cyclones were awful against the run in 2014, giving up an average of 5.67 yards per carry. Only New Mexico, New Mexico State and Georgia State allowed a worse average. The playing status of Iowa State's best returning defensive lineman, Mitchell Meyers, is also up in the air after he was diagnosed with Hodgkin's lymphoma. The Cyclones need a major impact from ESPN JC 50 defensive tackle Demond Tucker, as well as fellow juco addition Bobby Leath.