The No. 1 Clemson Tigers (13-0) are on the cusp of the second national title in the program’s history, but in order to repeat history for the first time in more than 30 years they’ll have to get past the No. 4 Oklahoma Sooners (11-1) in the College Football Playoff semifinal on Thursday Dec. 31.

As the first matchup in the four-team playoff to decide this year’s champion, the Orange Bowl enters the rotation as one of the major bowls to host a semifinal after sitting out last season, acting as host for the rubber-match between the ACC champion and undefeated Tigers and the Big-12 titleholder Sooners.

The two sides have met only four total times, splitting the all-time series 2-2, with Clemson winning the last two games including last year’s Russell Athletic Bowl 40-6 to hand the Sooners just their third five-loss season under head coach Bob Stoops.

Despite that victory and the current streak, Clemson and ACC Coach of the Year Dabo Swinny are early 3.5-point underdogs to Oklahoma for the matchup at SunLife Stadium in Miami Gardens, Florida.

Yet the Tigers have defied the odds all season to not only maintain their first perfect season since 1981’s singular national title run, but also cast away some of the country’s top programs in the process. Clemson was the CFP selection committee’s first choice for No.1 when the rankings first came out and it has held the distinction ever since.

Behind quarterback and Heisman Trophy finalist Deshaun Watson’s 30 touchdown passes and 11 rushing scores, Clemson upended then-No. 6 Notre Dame and No. 16 Florida State before scooting past No. 10 North Carolina in the ACC Championship.

With Watson at the helm of the offense and junior pass rusher Shaq Lawson manning the defense, the Tigers boasted the No. 15 attack in the country, netting 38.5 points per game, and the No. 18 defense with 20.2 points allowed per contest.

Lawson and redshirt junior end Kevin Dodd headline a devastating Clemson pass rush with a combined 17.5 of the unit’s 38.0 total sacks through 13 games. Their work has also helped leading defensive back Cordrea Tankersley and the secondary surrender a mere 166.9 passing yards and only 16 touchdowns this season.

But the Sooners can counter with the nation’s third-highest scoring offense (45.8 ppg) and quarterback Baker Mayfield, a junior who many felt should be joining Watson at the Heisman presentation ceremony Saturday.

Mayfield unleashed 35 passing touchdowns to only five interceptions, while completing 68.6 percent of his passed for 3,389 yards and gaining another 420 yards and seven scores to lead the Sooners to their first Big-12 title since 2012.

Mayfield’s joined by sophomore sensation and running back Samaje Perine, who was slowed by opposing defenses this season but still tallied 1,291 yards and 15 touchdowns for his second straight 1,000-plus yard season. And senior wide receiver Sterling Shepard ranked third in the Big-12 with 1,201 yards and 11 touchdowns.

The Sooners also have a talented pass rush and secondary to disrupt Watson just as much as Clemson has for Mayfield. Cornerbacks Zack Sanchez and Jordan Thomas pulled down 11 interceptions and defended 11 more for a secondary that ranked first in the Big-12 in passing yards allowed and in total defense.

Oklahoma also owned the best pass rush in the conference, tallying 38 total sacks with linebacker Eric Striker, defensive end Charles Tapper, and defensive tackle Charles Walker accounting for 20.5 sacks.

Betting Odds: Oklahoma -3.5

Over/Under: 65.5 points

Prediction: Oklahoma over Clemson, 35-30