The Thornton Academy boys’ basketball team was so dominant on the defensive end early in its Class AA South semifinal against Gorham that even surrendering 33 points in the final quarter couldn’t doom the Trojans.

Behind the strong defensive start, second-seeded Thornton was able to hold on for a 56-49 win at Cross Insurance Arena and will play for the regional title Friday against No. 1 South Portland.

The Trojans (17-2) surrendered just two points in the first quarter and only 16 through three quarters.

“Our team defense was really solid for the most part, especially early,” said Thornton Coach Bob Davies. “For the entire first half and most of the third quarter, our guys did a really great job being where they were supposed to be and rotating to help. Late in the third and in the fourth, we lost track of that and they hit some shots to stay in it, but defensively, the first half was just a great team effort.”

Thornton took control early, using a smothering defense to jump out to a 12-2 advantage by the end of the first quarter. John Fogg scored five of his 13 points, while Evan Christensen controlled the glass with five rebounds.

“It’s good to get some momentum going early,” said Davies. “If you play that type of basketball, you’re going to give yourself a chance to win.”

The margin was 23-10 at halftime, and then Christensen came to life offensively in the third quarter, scoring seven points as Thornton continued to shackle the sixth-seeded Rams (5-15) while pushing its lead to 30-16.

Jackson Fotter fueled Gorham’s furious comeback attempt, scoring 21 of his 25 points in the fourth.

“He had a really good game,” said Davies. “He’s a very good basketball player. He made some big 3s and did a good job getting to the hoop, and he really kept them in it.”

Fotter finished the fourth quarter knocking down seven of his 11 shot attempts, which included an impressive 4-of-5 showing from beyond the 3-point line to pace the 33-point attack.

Fotter was countered by Austin Boudreau, who got 14 of his 20 points in the final eight minutes.

“He gives them an offensive piece – a major offensive piece who knows how to score and create offense for himself or others,” said Gorham Coach Mark Karter. “We knew they had a mismatch against us with him and Christensen, and for most of the night we handled it pretty well, but he found a way to beat us.”

Boudreau also had five assists and three steals. David Keohan chipped in nine points and six rebounds, and Christensen had seven points and nine rebounds.

Cameron Holmes joined Fotter in double figures for Gorham, finishing with 11 points.