SAN JOSE, Calif.— A sophomore, a redshirt freshman and a true freshman walk onto a field. Two years and a national title later, they’re still there – despite opportunities to enter the NFL Draft – and will be seeking another championship ring at Alabama’s expense on Monday night.

Those three are Clemson defensive linemen Christian Wilkins, Clelin Ferrell and Dexter Lawrence, who along with senior Austin Bryant make up one of the most feared defensive lines in recent college football history.

“They’re game-plan wreckers,” senior running back Damien Harris said. “You watch them on tape and they have so many disruptive plays. They cause so much havoc for the offenses they’re playing. Their front seven is extremely physical, extremely talented.

“We know them, they know us; it’s going to come down to who plays the best fundamentally and who’s the most physical team.”

The Tigers’ defense allows the fewest points per game (12.9) in the 130-team FBS after holding No. 3 Notre Dame to three points in the Cotton Bowl on Dec. 29. It finished second in that statistic last season, trailing only Alabama, and 10th in 2016.

The constant through that stretch has been the defensive line. At one point last season, all four starters were projected as future first-round NFL draft picks.

“They’re big. They’re strong. They’re athletic. And usually you don’t really see that in teams that you play,” sophomore quarterback Tua Tagovailoa said. “It’s either one or the other. It’s either they’re just big or they’re just strong or they’re just athletic, but they kind of have a three-in-one package with almost all their D-linemen.”

Ferrell, who won this year’s Ted Hendricks Award as college football’s best defensive end, is projected as a top-20 pick if he forgoes his senior season.

Wilkins, the group’s elder statesman, has played in all 58 of Clemson’s games since the fall of 2015 and has twice been a finalist for the Nagurski Trophy, given annually to college football’s best defensive player. Neither he nor Ferrell has missed a game in their careers.

Lawrence, who at 350 pounds is the heaviest player on either team, has rarely missed a game in his three years, but he missed the Cotton Bowl after failing a drug test. Lawrence denied taking performance-enhancing drugs, saying he didn’t know how the supplement entered his system, but he was still suspended for both the Cotton Bowl and Monday’s national championship.

“(Lawrence) is a great player, tremendous, one of the best in the country at doing what he does,” Clemson coach Dabo Swinney said. “So I’m thankful that we’ve got Albert Huggins and some other guys… who are ready to go perform to the best of their ability. We certainly miss Dexter.”

The matchup between Clemson’s vaunted front four and Alabama’s offensive line, which has been a finalist for the Joe Moore Award for four years running, promises to be one of the most crucial in determining which team leaves Levi’s Stadium with the trophy.

“It’s going to be a huge challenge for us up front,” senior center Ross Pierschbacher said. “We know those guys well just playing against them for a while and they know us. It’s just going to come down to execution and physicality up front. The game will be won in the trenches, so that’s how we like it.”