COLUMBIA — It wasn’t not the path to 12-0 top-ranked Clemson thought it was going to take on Saturday in Columbia against a South Carolina team that had lost four straight and was 3-8 coming in.

The momentum was on South Carolina’s side. The Gamecocks has just scored on a Shon Carson 1-yard run to cut what was an 18-point lead to three points with 12:19 to play in the game. But not to worry, Clemson had Deshaun Watson playing quarterback.

“He was unbelievable, again. He was the difference in the game,” Clemson head coach Dabo Swinney said.

On the ensuing possession, the Tigers faced third down-and-nine from its own 41-yard line, and Watson hit tight end Jordan Leggett up the far sideline for 12 yards and a first down. Again facing a third down four plays later, this time on third-and-seven from the USC 33, he threw a dart to Trevion Thompson for 24 yards to the nine-yard line.

Three plays later, again on third down, Watson ran off the left side and dove into the end zone for his third rushing touchdown of the game and fourth overall. The touchdown was all the Tigers needed as they held off a pesky Gamecock team for a 37-32 victory.

“Nobody panicked. It’s just football, it’s what we do,” Swinney said. “We had a situation where we could have just got five yards and kick a field goal, but we’re here to try and win a national championship. We hit a big play to keep the drive going and later we get a touchdown.”

Clemson improved to 12-0 for just the second time in school history with the victory, matching the 1981 team’s record. It was also the last time the Tigers finished the regular season with a perfect record. They have now won 15 straight games, the nation’s longest winning streak, tying the 15-game win streak the 1947-’49 Tigers set.

Clemson will play No. 11 North Carolina next Saturday in Charlotte for the ACC Championship. A win there and the Tigers are headed to their first appearance in the College Football Playoffs.

“It is great to be state champs again, and I’m very happy for our fans,” Swinney said. “This team has a chance to stand alone among Clemson greats.”

As for Watson, he finished the day with 393 total yards and four touchdowns. He had a second quarter 55-yard touchdown pass to Deon Cain as well.

Watson finished the day 20 of 27 for 279 yards, while rushing for 114 yards on 21 attempts.

“That’s what great players do, they make everyone else better,” Swinney said. “He is certainly a great player. At this stage he is pretty special. I think he is the best player in the country. He just doesn’t flinch, he keeps grinding and he makes good decisions.”

South Carolina (3-9) took advantage of three Clemson turnovers to stay close. But the Gamecocks also showed some life on offense for the first time this season. Their 32 points was the most points they had scored all season.

“We were their best defense there for a little while,” Swinney said. “But we finally settled in and took care of the football.

USC finished with 402 total yards, the most yards gained against Clemson since the Notre Dame game on Oct. 3. The Tigers had 515 total yards in the victory — 236 rushing and 279 passing. The Tigers were 9 of 13 on third down.

“We felt we could spread them out and create some matchup problems and we were able to do that,” Swinney said.