SEC games are won up front, in the trenches.

The following four units return a majority of their linemen and, in most cases, were in the top half of the SEC in 2015.

Some have already made the Associated Press All-SEC teams, while others flirted with the NFL. What they have in common is experience, accolades and the ability to disrupt the opponent’s game plan.

Here are the four scariest lines in the SEC in 2016.

Alabama defensive line

Jonathan Allen made the All-SEC first team and was considered a first-round pick but decided to return to Alabama in 2016. Combined with Tim Williams, the Crimson Tide could have two of the best pass rushers in the country.

After all, Allen led the team last season in sacks (12) and tackles for a loss (14.5), and Williams was second with 10.5 sacks. And while Williams is a hybrid defensive end/linebacker, another versatile budding star is Rashaan Evans, who sacked Clemson’s Deshaun Watson twice in the national championship.

Da’Shawn Hand, who also had a huge championship game, is due for a breakout year after he had three sacks and 6.5 tackles for a loss in 2015.

A notable signee this year was 375-pound Kendell Jones from Texas. Nicknamed “The Hulk,” Jones is much heavier than his new teammates, but could pair well with backup Joshua Frazier, who is 315 pounds and looking to crack the starting lineup, along with Da’Ron Payne, another 300-pounder.

Auburn offensive line

The Tigers return the majority of their offensive line, including center Austin Golson, right guard Braden Smith and left guard Alex Kozan. That’s a sigh of relief for new position coach Herb Hand because Smith and Kozan started every game in 2015, and Golson started 10. Smith was named second team All-SEC.

Combined, they have 73 appearances.

They were part of a unit last year that was fourth in the SEC in sacks allowed and fifth in rushing offense at 196 yards per game.

Texas transfer Darius James, the projected starter at right tackle, is a former five-star recruit who has recovered from a knee injury with the Longhorns. If injuries or lineup changes are an issue, Auburn redshirted five linemen last year. Hand has options at left tackle, including fifth-year senior Robert Leff, redshirt freshman Mike Horton and James.

Arkansas defensive line

While much of the offseason discussion has centered on the departures on the offensive line, the Razorbacks return a defensive front that includes Deatrich Wise Jr., Jeremiah Ledbetter and Tevin Beanum.

They combined for 12 sacks in 2015, led by Wise’s eight.

What’s more, all but one player off last year’s two-deep depth chart returns, and Arkansas brings in five-star defensive end McTelvin Agim.

The 2015 Arkansas defense was second in the SEC in rushing yards allowed per game. After some interest from the Philadelphia Eagles, defensive line coach Rory Segrest was among three assistants to receive raises as he now makes $300,000 a year, the Arkansas Democrat-Gazette reported.

Tennessee offensive line

Four starters are back and they’ll be a big reason Tennessee’s skill players have any level of success in 2016.

That line in 2015 was second in the SEC in rushing offense at 223 yards per game. After 10 games, the Volunteers had already eclipsed (2,103) the previous season’s 13-game total (1,903). They finished with 2,908.

Among those returnees is guard Dylan Wiesman, who made the Associated Press All-SEC second team. Another returnee, Brett Kendrick, is trying to avoid the elbow and shoulder injuries that impacted last season and limited him him to seven games and five starts. Jashon Robertson’s return from an ankle injury was highlighted after Jalen Hurd’s career night in a win over Missouri.