SACO — On the opening play Saturday, Thornton Academy running back Greg Ruff gained 69 yards. It was a sign of things to come.

Ruff, a senior, torched Scarborough for 207 yards rushing and two touchdowns in the first half as the defending Class A state champions built up a 28-0 halftime lead against Scarborough.

Ruff got one more carry in the third quarter, a 25-yard run, before calling it a day as Thornton rolled to a 35-0 win in a Class A South semifinal.

The top-ranked Golden Trojans (8-1) will play third-seeded Bonny Eagle (7-3) for the regional championship at 1 p.m. Saturday. It will be the third straight year the teams have met for the regional title, with each team winning once on the way to a state championship.

Ruff broke off left tackle on his first carry, got outside and wasn’t hauled down until he reached the Scarborough 9. Quarterback Austin McCrum scored on the next play.

Ruff scored on a 41-yard run at the end of the first quarter. He also had runs of 22, 15 and 20 yards in the first half.

“It was Greg’s day to shine,” said Thornton Coach Kevin Kezal. “That was a great first drive and a great first-half performance by our team.”

With the wind gusting the entire game, it was a tough day to throw.

“I was happy to have the running game working so well with Greg and Michael Laverriere,” said McCrum.

When he did have the wind at his back, McCrum took advantage. Late in the second quarter, he fired a pass over the middle to Corey Hart, who nearly made it to the end zone before being stopped at the 3. The play covered 46 yards. On second down, Laverriere scored from the 3 with nine seconds remaining in the half, giving the Trojans a 28-0 lead.

It was a crippling blow for Scarborough (5-5).

“We had our opportunities in the first half,” said Scarborough Coach Lance Johnson, whose team lost to the Trojans 48-7 during the regular season. “Aside from Thornton scoring in only two plays, I thought we played well and stayed with them.

“Thornton is a very good team. We threw an interception in the end zone and we missed a couple open receivers. At least we played harder than the last time we played them.”

While Ruff was the running star, Laverriere also was a big contributor as his role continues to increase.

“He’s finally healthy,” Kezal said of Laverriere.

Thornton had two interceptions in the first half, including an acrobatic grab by Ben Lambert after the Trojans had built a 14-0 lead.

An interception by Cam Cadorette stopped Scarborough’s best scoring threat a few minutes later, after Jack Hughes passed to Connor Kelly for a 33-yard pickup to the Thornton 15. Two plays later, Hughes overthrew his receiver and Cadorette intercepted the pass in the back of the end zone.

The Golden Trojans then drove 80 yards in 12 plays, culminating in Ruff’s 1-yard run that made it 21-0.

Kelly had a one-handed interception for the Red Storm in the first quarter.

Laverriere finished 52 yards on 10 carries. McCrum completed 4 of 12 passes for 81 yards.