SWANZEY CENTER — In the regular season, Trinity proved to be one of Monadnock’s toughest opponents on the lacrosse field, battling the Huskies to a 13-9 decision.

But in the playoffs, the Pioneers were no match for the green and white.

No. 3 seed Monadnock crushed No. 6 Trinity, 17-4, on a cleared-off section of Main Field Saturday in the Division III quarterfinals, advancing to the semifinals for the third straight year. The Huskies face No. 2 seed and two-time defending state champion Hopkinton — one of two teams to beat Monadnock in the regular season — Wednesday at 5 p.m. at Bank of N.H. Stadium at Laconia High School.

“I think we just came out a lot more prepared,” said Monadnock senior co-captain Tim Hart, who had six goals and one assist. “I think we just had it in the back of our minds that they had a close game with us last time, so we figured they were gonna come out gunning, thinking they actually had a chance today, and we knew we had to start off scoring right away. ... I think we did a pretty good job with that.”

The Huskies set the tone early, quickly going up 2-0 on goals by Dominic Dow (six goals, one assist) and Chris Boucher (two goals, five assists). Then, after Tom Pouliot committed a foul on the back end, the Monadnock defense sent its first clear message, quelling Trinity’s power play and keeping the Pioneers off the scoreboard for all of the first quarter and the first half of the second.

The Huskies led 8-0 by the time Trinity scored its first goal.

After his team struggled to cover the Pioneers’ open-formation offense in the regular season, Monadnock Coach Rob Hart said adjustments made by defenders Cole Elfreich, Isaac Jasinski, Jackson Lepisto and Pouliot were perhaps the biggest factor in the Huskies’ playoff win.

“I think just their positional defense and staying with their men,” Hart said. “Last time, I think we did a lot of ball-watching, and they did a lot of back-door, back-side cuts on us. This time, guys really got in position and stayed with their men, and I think they communicated about the best they have all year.”

When the second quarter began, however, it was the offense that stole the show. Monadnock scored three goals in the first 1:12, with two coming from Dow and one from Tim Hart.

The Huskies run a matchup-based offense where any number of different players could wind up being the team’s go-to scorer, and Saturday it was Dow and Hart’s turn. The pair combined for seven goals in the first half (four from Dow, three from Hart) to give Monadnock a 10-1 lead at the break.

“The draw-and-dump was working a lot,” Dow said. “They would double-team (someone else), and then I’d just be wide open.”

Boucher was the Huskies’ leading scorer during the regular season — scoring five or more goals four times and 10 goals in one game — so he drew plenty of attention from the Trinity defense. But he was more than happy to play the facilitator role, making highlights with his passes instead of his shots.

“It’s wicked helpful when you’re not the only guy out there trying to do everything,” Boucher said. “Kind of just sitting back and watching them and reading what they’re playing, their cuts and stuff, it’s a lot easier to play, and being able to rely on them is definitely very helpful.”

Aidan Hart added two goals and one assist, and Chandler Matson recorded one goal and two assists.

The semifinals have been the last stop for the Huskies each of the last two years — losing last year to Laconia, 11-5, and the year before to Kearsarge, 8-7. Hopkinton — which beat Kearsarge and Laconia in the state finals after it ended Monadnock’s seasons — narrowly beat the Huskies in an April 22 game in Hopkinton, 15-14.

Several Monadnock players know what it means to come close to a title, only to fall short, and their experiences come from more than just one team.

Boucher, Dow, Jasinski, Elfreich, Lepisto, Justin Joslyn, William Lepisto, Alex Hudon and Austin Wyman all played for the Huskies boys’ ice hockey team that went to the state finals this past winter, only to lose to John Stark-Hopkinton, 1-0.

“It’s a chip on our shoulder,” Boucher said. “We’re gonna try and go as far as we can. For us seniors, it’s our last season in high school, so we’ve got a lot of things behind us, pushing us, so our motivation’s pretty high.”

But many also know what it means to triumph in the end.

Matson, Jasinski, Elfreich, Joslyn, Wyman, Joey Drew, Dylan Cashman, and both Tim and Aiden Hart were on Monadnock’s state champion football team this fall.

“The chance to win another one just really drives you, because you already know what the feeling is,” Tim Hart said. “So, to have the chance to get another one is really gonna make everybody go full throttle and get it.”

The journey continues Wednesday in Laconia.