The offensive line is often the most overlooked position for any college football team. While the linemen in the trenches don’t get enough credit, they are often the most important piece to a successful offense. Flashy skill talent and quarterbacks take home all of the accolades and headlines, but neither position can thrive without a solid offensive line.

Which teams are strongest in the trenches heading into the 2015 season? Five SEC teams rank among college football's best lines, while Ohio State and Michigan State give the Big Ten two teams inside of the top three.

Related: College Football's Top 50 Players for 2015

How did we come up with these rankings? A couple of factors were considered. Depth, overall talent, production, level of competition and projected output in 2015 all factored into the rankings for the backfield. While some teams may have experienced a down year last season, having a different quarterback or a change of scheme can make a huge difference. These rankings reflect projection for 2015, not solely what teams have accomplished in 2014.

CFB's Top 30 Offensive Lines for 2015

New line coach Rob Sale couldn’t ask for a better way to begin his tenure in Athens. This unit allowed only 12 sacks in SEC games and excelled in run blocking by clearing lanes for rushers to average 6.0 yards per carry. All-SEC center David Andrews will be missed, but Sale’s group is set with the return of rising star Greg Pyke at guard, along with the standout tackle duo of John Theus and Kolton Houston. Brandon Kublanow is the favorite to replace Andrews at center.

The Spartans boasted one of the nation’s top offensive lines last season, and this unit is only getting better with the return of four starters, along with the emergence of sophomore guard Brian Allen. Left tackle Jack Conklin and center Jack Allen headline a group that gave up only 11 sacks last season and allowed rushers to average 5.2 yards per carry. Senior guard Donavon Clark and right tackle Kodi Kieler anchor an experienced right side.

After a shaky start to the 2014 season, no line in the nation progressed as much as Ohio State’s. The Buckeyes gave up seven sacks in the loss to Virginia Tech in Week 2 but allowed only 15 sacks in Big Ten games, and quarterback Cardale Jones was sacked once in the national title win over Oregon. Four starters are back, and the Buckeyes expect this group to be even stronger. Left tackle Taylor Decker and right guard Pat Elflein are the unit’s top performers and first-team Athlon Sports All-Americans for 2015. Jacoby Boren returns at center, while Billy Price (left guard) and Chase Farris (right tackle) round out the starting five.

Related: College Football Bowl Projections for 2015

The success of Baylor’s high-powered offense starts in the trenches. Left tackle Spencer Drango considered an early jump to the NFL, but the three-year starter is back and is a first-team Athlon Sports All-American for 2015. Three other seniors join Drango up front, including guard Blake Muir and tackle Pat Colbert. Center Kyle Fuller started all 13 games last year and will push for all-conference honors in 2015. The coaching staff wants to develop more depth, but there are few concerns about the starting group. This unit gave up only one sack every 22 pass attempts and allowed Baylor rushers to average 4.5 yards per carry.

The Razorbacks return four starters from the nation’s largest offensive line. This unit cleared the way for rushers to average 5.1 yards per carry and allowed only 14 sacks in 2014. All five projected starters for 2015 weigh over 300 pounds, with converted guard Denver Kirkland slated to anchor the line at left tackle. Kirkland and Dan Skipper are among the SEC’s best up front, and the tackle duo will have plenty of support from the starters on the interior. Sebastian Tretola is a mauling 322-pound guard, and senior Mitch Smothers enters 2015 with 21 career starts. Sophomore Frank Ragnow is the only new starter for this unit.

Related: SEC Coaches Talk Anonymously About Conference Foes for 2015

The Tigers must replace standout center Reese Dismukes and guard Chad Slade, but this unit remains a strength for coach Gus Malzahn. Three starters are back, including tackle Avery Young and left tackle Shon Coleman. The return of guard Alex Kozan from a back injury should bolster the interior, while Austin Golson and Xavier Dampeer are locked into a tight battle to replace Dismukes at center. Promising sophomore Braden Smith is expected to start at right guard. This unit allowed only 10 sacks in SEC play last season.

LSU’s passing offense is once again surrounded in mystery. However, there’s no doubt about the strength of the Tigers’ offense. The rushing attack should be among the best in the SEC and is anchored by rising star Leonard Fournette. The line is also a big part of LSU’s success on the ground, as three starters return from a unit that helped the Tigers average 224.5 rushing yards per game in 2014. Tackles Vadal Alexander and Jerald Hawkins are among the best in the SEC, while Ethan Pocic (a returning starter) is penciled in at left guard. Freshman Will Clapp (center) and Garrett Brumfield (right guard) should round out the starting five.

Related: Ranking the SEC's Top 15 Players for 2015

The Crimson Tide’s offensive line is undergoing some renovations with the loss of three starters. However, line coach Mario Cristobal has plenty of talent to develop, while the two returning starters – left tackle Cam Robinson and center Ryan Kelly – are among the best in the nation at their position. Redshirt freshman Ross Pierschbacher is expected to start at left guard, while Bradley Bozeman and Alphonse Taylor are battling for snaps at right guard. Senior Dominick Jackson has the inside track at right tackle.

The Trojans need to settle on a starting five, but this unit has plenty of promise and talent leading the way for one of the nation’s top offenses. Solidifying the left tackle position is critical, as junior Chad Wheeler is working his way back from a knee injury suffered in 2014. Toa Lobendahn could start at left tackle if Wheeler isn’t ready, or the talented sophomore could shift inside to left guard. Max Tuerk is arguably the nation’s best center, while the Trojans also boast returning starters at right tackle (Zach Banner) and right guard (Viane Talamaivao).

Related: Ranking the Pac-12's Top 15 Players for 2015

Protecting quarterback Trevone Boykin won’t be a problem for TCU in 2015. The Horned Frogs return four starters from a unit that allowed 23 sacks in 13 games last season. Hala Vaitai missed time in the spring due to a shoulder injury, but the senior is penciled in at left tackle after starting on the right side last year. Center Joey Hunt is among the nation’s best, while fellow seniors Jamelle Naff and Brady Foltz round out the returning starters.

11. Stanford

12. Notre Dame

13. Texas Tech

14. Boise State

15. Georgia Tech

16. UCLA

17. Missouri

18. Texas A&M

19. Ole Miss

20. Oregon

21. Pittsburgh

22. Wisconsin

23. Kansas State

24. Indiana

25. North Carolina

26. Minnesota

27. Oklahoma State

28. Michigan

29. Texas

30. Bowling Green