LEWISTON — Depth was the enemy for the Marshwood/Traip Hawks on Saturday.

It was a welcome ally for a streaking Thornton Academy squad.

Using a relentless attack, the Trojans weathered an early wave of pressure from the Hawks, and ran away from the undermanned, third-seeded co-op program with four goals in the final frame, posting an 8-1 win in the team’s Western Class A semifinal matchup at the Androscoggin Bank Colisee.

Showcasing a set of four lines, the Trojans’ final two goals — scored in a 30-second stretch of the third period — went in courtesy of a seventh defenseman-turned-forward and his linemates on the fourth trio for TA.

Sam Canales finished with two goals for Thornton to lead the attack. The Trojans advance to the Western Class A final Tuesday at the Colisee against Biddeford.

Despite a flurry of activity from the Hawks — and a pair of golden opportunities to score — the Trojans skated into the first break with a 1-0 advantage, courtesy of a quick slapper from Dakota Matthews on a faceoff win by C.J. Maksut at the right offensive circle, to Gagnon’s left.

Marshwood/Traip’s best opportunity to find the net early came on a delayed penalty at 12:05 of the first, when freshman Peter Lajeunesse rang the iron after slipping through a pair of defenders.

Gagnon was solid at the other end for the Hawks, too, stuffing Sam Canales on a good backhand deke move on a 2-on-1 late in the first frame.

“It was a funny first period,” Thornton coach Shawn Rousseau said. “I think that (Marshwood/Traip) played this game as well as they could have played. What good teams do is force other teams out of their system of play. And we had to make three significant adjustments in this game, not because we were not executing well, but because Marshwood/Traip was forcing us to try something different.”

The Trojans pulled away in the second. After a long stretch of power play time for the Hawks — including a 49-second stretch of 5-on-3 action — which resulted in a handful of shots and no goals, Canales struck on a rebound goal on the power play for Thornton to put the Trojans on top by two. Robbie Downing made it 3-0 TA 1:07 later with a snipe to the top shelf glove side.

Aaron Gootee threatened to make things interesting at 11:46 of the second, pulling his squad briefly to within a pair on a power play goal, but Thornton’s C.J. Maksut nixed those comeback ideas with a goal of his only six seconds later off the faceoff, giving the Trojans a 4-1 advantage after two periods.

“That was the game right there,” Rousseau said.