KITTERY — In a semifinal matchup of former Western Class C cellar-dwellers turned contenders, Traip Academy firmly put itself a step ahead Saturday.

Second-ranked Traip forced four turnovers and posted its second playoff shutout and fifth of the season in a 21-0 semifinal victory against third-seeded Maranacook.

The Rangers (8-2) will play at top-ranked Yarmouth (10-0), the defending state champion, in the regional final at 12:30 p.m. Saturday.

For Traip, it was another significant stride away from a 51-game losing streak its current seniors snapped when they were freshmen. Maranacook (8-2) was 0-8 four years ago.

“Incredible. Incredible. We’ve talked about it since we were in seventh and eighth grade. We said that we were going to be the class to lead to the championship, and nobody thought we could do it and we’re on the (way),” said Traip senior fullback/linebacker Tyler Nay.

A tough 2-yard touchdown run by Nay and his 2-point conversion capped Traip’s first second-half possession.

“Look at where we’re going. (Zero) and 51 to (a title game)? Really?” Traip Coach Ron Ross said. “You’re only as good as your seniors and we say it all year long, and our seniors are pretty damn good. So here we are, you know. They got us here and they’re taking us to the next level.”

Cory Aldecoa also helped. He lugged the ball 34 times for 199 yards, including a 14-yard run for Traip’s first touchdown.

Some of his best work came when Traip went to an unbalanced line with both its tackles, Dan Eddy and Ben Castellano, on the left side with guard Pat Norton. Traip gained 279 yards, all on the ground.

“Our line is outstanding,” Ross said. “That’s not a Class C line right there. That’s a Class A line, I don’t care what anybody says. All they did all offseason was get bigger, stronger, faster, and if you can’t run behind that line you shouldn’t be coaching.”

Traip made it 13-0 on a 1-yard run by quarterback Matt Clifford midway through the second quarter.

Disdaining its running game early, Coach Joe Emery called more than 25 pass plays despite saying he was without his best receiver Seth Miller (injured), and that his second-best pass catcher, tailback Luke Emery, was limited by an ankle injury. Quarterback Caleb Castonguay finished 6 of 21 for 54 yards with two interceptions.

“Traip’s a really good team, and I had four starters go out in the last week and a half and I just couldn’t plug the dam anymore,” Emery said. “I thought we could do a really good job passing and we didn’t get it done today. We didn’t execute and Traip did, as simple as that.”

Traip twice stopped the Bears in the red zone with turnovers.

“We caused turnovers today and we didn’t have any turnovers,” Ross said. “(Maranacook) supposedly had the better defense. Our defense took that personal. Actually we took a lot of things personal this week.”