MANCHESTER — Trinity High School running back John Thibault has been demolishing opposing defenses all season long, and Saturday was no different.

The standout senior rushed for 234 yards and scored three touchdowns to lead the second-seeded Pioneers over No. 6 Stevens, 48-15, in an NHIAA Division III semifinal game at Derryfield Park.

Thibault ran for a 76-yard touchdown on Trinity’s first offensive play from the line of scrimmage, setting the tone for a field day against the Cardinals (6-5).

“He’s just a phenomenal running back,” said Stevens coach Paul Silva. “He’s physical and he’s elusive, he’s fast and he’s just hard to get on the ground.”

Thibault, who played for Newport High his first two years, added a second touchdown, which his younger brother, James Thibault, followed with a TD run of his own before the visitors got on the scoreboard.

The Cardinals’ first successful drive began midway through the second quarter on a 14-yard run by Keaghan McAllister (108 total yards).

McAllister, Lucas Mudge and Matt Jones each made significant carries on the 16-play march, which also included a 17-yard pass from quarterback Owen Taylor to receiver Alex Taylor. McAllister was stuffed a few times near the goal line before ultimately jumping up and over the pack to break the end-zone plane in horizontal fashion. Clayton Wadsworth booted the extra point, and the Cardinals trailed, 21-7, with 17 seconds remaining in the first half.

Trinity (10-1) quickly regained the momentum, however, when Dantre Taylor returned the ensuing kickoff 45 yards to set up a field goal by Liam McCoy.

John Thibault’s early rushing dominance paved the way for the Pioneer’s passing game, led by quarterback Peter Alisandro. The latter connected with Taylor for a 50-yard gain in the opening series of the third quarter.

The hosts added two more touchdowns before Stevens scored on a drive that began with Pascal Lemieux’s 18-yard kickoff return. Two McAllister rushes and an incomplete pass later, Owen Taylor ran for 36 yards on a quarterback keeper, setting up a 4-yard TD run by McAllister. Taylor then completed a pass to Quentin Bicknell for a two-point conversion.

Stevens, which lost to Trinity, 36-13, during the regular season, never let up despite being overmatched on Saturday.

“Character is easy to display when things are going good, but when things aren’t going good and when things really aren’t going good, that’s when you find out what you’ve got,” Silva said. “And I thought these guys fought until the end. We could have just said, ‘Hey, it’s not our day,’ but we fought and got in the end zone again, and I’m just really proud of the guys.”

Silva’s lengthy postgame address was followed by numerous hugs and handshakes among adjourning teammates.

“Football is an amazing sport,” said McAllister, who amassed 1,462 rushing yards and scored 27 touchdowns on the season. “Kids come and join. It’s not just joining a team; they join a family. It’s just hard, a loss like this is … so hard.”

Trinity’s victory sets up a rematch with Lebanon, which won the teams’ regular-season meeting, 21-7, at Lebanon High. The title game will be played next Sunday morning at UNH.

“Lebanon’s a good, strong, tough team,” fourth-year Trinity coach Robert Cathcart said. “They have a lot of good athletes at multiple positions. I don’t think they have a weak spot offensively or defensively. They just have 11 guys that can line up and play football and they’re tough, and we had a tough time with them (in the regular season), and I’m sure it’s going to be tough going into this one.”

Like everyone else on the Pioneers’ schedule, the top-seeded Raiders will be keying their defense on John Thibault.

“There’s been a lot of coverage in the papers about all kinds of different backs in the state and what great years they’re having, and we happen to think that we have the best back,” Cathcart said. “We are guilty a little bit earlier in the season: We’ll pull him and not have him play the whole damn game, so he doesn’t have touchdowns that ring through the roof because we’re careful with him.

“But in terms of yards per carry, I’m sure he’s one of the best ones. He’s rushed for over 2,000 yards on the season, so he’s a damn good back and we’re happy to have him.”