The first College Football Playoff semifinals produced a championship-worthy performance — at least in the Sugar Bowl.

Fourth-seeded Ohio State was a nine-point underdog to Alabama, but the Buckeyes defied the oddsmakers and overcame an early 15-point deficit to beat No. 1 seed Alabama 42-35 on Thursday night in the Mercedes-Benz Superdome.

“We believed in ourselves,” said Ohio State linebacker Darron Lee, the game’s Defensive MVP. “We believed in ourselves when everyone in the nation doubted us.”

Ohio State will play Oregon, which blasted Florida State 59-20 in the other semifinal at the Rose Bowl, in the CFP Championship Game Jan. 12 in Arlington, Texas.

“It’s just like another team,” Ohio State defensive back Vonn Bell said of Oregon. “We’re going to line up and strap up, too. I’m just proud to be a Buckeye.”

The Buckeyes, champions of the Big Ten, won their 12th in a row — best in the nation — to improve to 13-1 after winning their first bowl game against an SEC opponent in 11 tries.

“This was a breakthrough win against an excellent football team,” said coach Urban Meyer, who won two BCS championships as coach at Florida.

The Crimson Tide, champion of the Southeastern Conference, finished 12-2.

“It’s a great win any time you can beat a team of Alabama’s quality,” cornerback Eli Apple said. “We just have to keep balling. We have one more to go. That’s all we’re thinking about right now.”

The Buckeyes will meet the Pac-12 champion Ducks in the first title game not to feature an SEC team since Texas beat USC after the 2005 season in the Rose Bowl.

Unlike the lopsided semifinal at the Rose Bowl, this one wasn’t decided until Tyvis Powell intercepted Blake Sims in the Ohio State end zone with no time left.

“We played awful at times and didn’t play the type of Ohio State football that we preach,” Meyer said. “We overcame that with some excellent effort. This is one of the great team efforts we’ve been a part of.”

Buckeyes quarterback Cardale Jones, a redshirt sophomore making just his second collegiate start — he threw three touchdown passes in a 59-0 rout of Wisconsin to win the Big Ten title last month — outplayed Sims. Jones completed 18-of-35 passes for 243 yards and a touchdown. He threw one interception and ran 17 times for 43 yards.

But it was running back Ezekiel Elliott, who ran for 230 yards and two touchdowns on 20 carries, who was named Offensive MVP.

Sims was 22-of-36 for 237 yards and two touchdowns but was intercepted three times. He ran 10 times for 29 yards and a touchdown.

“Man, he just balled out,” Apple said of Sims. “He showed a lot of heart out there.”

Ohio State was clinging to a 34-28 lead when it punted from its end zone in the middle of the fourth quarter. With reduced room to work with, Cameron Johnston rushed his punt, and the ball kicked back toward the Buckeyes goal line after hitting the turn. It was downed at the Ohio State 23, but on the next play Bell intercepted a Sims pass at the 1 and returned the ball to the 8.

The Buckeyes couldn’t get a first down and punted to the Crimson Tide, which took over at its 45. Alabama moved to the Ohio State 40, but on third-and-6, Sims was tackled for a 3-yard loss.

The Tide punted and downed the ball at the Buckeyes 5 with 5:24 left. Four plays later, Elliott sprinted 85 yards for a touchdown, and a two-point conversion gave the Buckeyes a 14-point lead with 3:24 left.

Sims threw a 6-yard touchdown pass to Amari Cooper — a Heisman Trophy finalist who had two touchdowns but just 71 yards on nine catches — to make it 42-35 with 1:59 left, but Ohio State recovered an onside kick.

The Crimson Tide got the ball back at its 18 after a punt with 1:33 left and reached the Ohio State 42 before Sims’ Hail Mary went unanswered.

“I’m very proud of this team,” Alabama coach Nick Saban said. “They executed all season long and kept Alabama at the forefront of college football. We’re disappointed in tonight’s game.”

Ohio State, which scored two touchdowns in a span of 2:33 to get within a point at halftime, carried that momentum into the third quarter. On the first possession, Jones threw a 47-yard touchdown pass to Devin Smith to give the Buckeyes a 27-21 lead.

Steve Miller’s 41-yard interception return for a touchdown increased Ohio State’s lead to 34-21 with 3:21 left in the third.

Alabama stopped a 28-0 run as Derrick Henry turned a short pass from Sims into a 52-yard gain, leading to Sims’ 5-yard touchdown run. That left the Buckeyes with a 34-28 lead entering the fourth quarter.

Ohio State had early opportunities, but Alabama was more opportunistic.

On their first possession, the Buckeyes drove to a first-and-goal at the 5 but couldn’t gain another yard and settled for a Sean Nuernberger 22-yard field goal and a 3-0 lead.

The Crimson Tide didn’t get a first down on either of its first two possessions, but Landon Collins recovered an Elliott fumble, giving Bama the ball at the Ohio State 33. Two plays later, Henry ran 35 yards for a touchdown.

Jones’ 40-yard pass to Smith helped the Buckeyes reach the Tide 1, but they went backward before Nuernberger kicked a 21-yard field goal.

Bama followed that with its first sustained drive, a 79-yard march that ended with a 15-yard touchdown pass from Sims to Cooper.

Another Ohio State turnover led to another Alabama touchdown as Cyrus Jones snared a Jones pass at the Buckeyes 47 and returned to the 15, leading to T.J. Yeldon’s 2-yard touchdown run.

“Really, we were up 21-6 because of two turnovers and two stops in the red area,” Saban said. “So we really weren’t stopping them. We kind of had the momentum of the game because of the turnovers that we got and converted those into scores. But we weren’t really playing and executing the way we needed to even then. I didn’t like the feel of the game even then.”

Ohio State finally reached the end zone late in the second quarter, completing a 71-yard drive with Elliott’s 4-yard touchdown run.

The Buckeyes drove 77 yards on their next possession and wide receiver Evan Spencer threw a 13-yard touchdown pass to Michael Thomas with 12 seconds left, cutting Alabama’s lead to 21-20 at halftime.