Sam Farrell said his Brunswick girls’ basketball players believe in their defense.

That was certainly evident Monday afternoon when the second-seeded Dragons defeated No. 7 Kennebunk 57-42 in a Class A South quarterfinal at the Portland Expo.

The taller Dragons built a big early lead with defense and rebounding and then held off a second-half Kennebunk rally to advance. The Rams, in the tournament for the first time in 10 years, hit just 26 percent of their shots in the game and were especially cold early, hitting just one of their first 13.

“I thought that was the difference,” said Kennebunk Coach Rob Sullivan. ‘That’s just the difference between a team that’s been here and a team that’s been fighting like heck to get here. The effort was there, we just didn’t execute early.

“We made some nice plays later, but we built too big of a hole.”

Brunswick (16-3) will play third-seeded York in the regional semifinals at 1 p.m. Wednesday at Cross Insurance Arena.

Kennebunk finished 8-11.

Madeline Suhr led Brunswick with 16 points, 11 rebounds and three blocked shots. She felt the difference between this game and the regular-season game – an overtime Brunswick in overtime – was defense.

“We just shut down the shooters,” she said. “We knew who the shooters were and we did it pretty well.”

“We played good help defense,” said Farrell. “You get good ball pressure with good help. … I don’t know if they got a good open look. When five girls move together, and using our length, it’s a good thing.”

Brunswick led 14-4 after one quarter when Suhr hit a 3-pointer from the right wing. In the second, with the Dragons in foul trouble, Rosalie White came in to score eight points – six on offensive rebounds – to help the Dragons take a 33-16 halftime lead.

“The tournament’s all about kids stepping up and making plays,” said Farrell. “And we had enough kids do that.”

Kennebunk finally made a run in the third, pulling within 39-29 with 2:11 left in the quarter on a foul shot by Madi Lux. But Suhr scored on a successive fast breaks to regain Brunswick’s momentum, and when Brooke Barter hit her second 3-pointer of the game to start the fourth, Brunswick was back in control.

Barter and Sabrina Armstrong each scored 10 points for Brunswick. Sierra Tartre led Kennebunk with 14 and Gabby Fogg added 10.