AUGUSTA — In the Class C South girls’ basketball quarterfinals, top-seeded Boothbay struggled to put away St. Dominic Academy. But the Seahawks weren’t concerned about a carryover Thursday afternoon against Madison in the semifinals.

“No,” Boothbay Coach Brian Blethen said. “No doubts, and that was the message. We didn’t want to leave any doubt in anyone’s mind. Yes, we had a bumpy quarterfinal game, but we know what we’re capable of doing and how we want to play.”

Boothbay dominated No. 13 Madison at the Augusta Civic Center, cruising to a 55-23 win. Boothbay (20-0) will face No. 3 North Yarmouth Academy (16-4) at 7 p.m. Saturday.

Madison finished 7-14.

Boothbay scored the first 20 points and led 20-1 after one quarter. The Blethen sisters, 6-foot-1 senior Faith and 6-2 sophomore Glory, controlled the game, and the Seahawks dictated the pace.

“We needed to be assertive on offense and not play tentative as we did in the quarterfinal game. That’s what we worked on,” Coach Blethen said.

Glory Blethen scored 13 of her 20 points in the first half as Boothbay built a 35-7 lead. Faith Blethen, a semifinalist for Miss Maine Basketball, had a quiet double-double with 11 points and 12 rebounds.

“They have two players who are taller than all of our team. They do some good things,” Madison Coach Al Veneziano said. “You’ve got to come up and be aggressive with them. I thought we laid back a little bit, but hey, that’s the way it is.”

Emily Edgerly led Madison with eight points.

The Bulldogs upset No. 4 Hebron Academy in the preliminary round, then beat No. 12 Traip Academy in the quarterfinals. Just reaching the playoffs was a goal for a Madison team that began the season short on varsity experience.

“I’m very pleased with how the kids have played the last few weeks. We came back with no starters on our team this year. Lauria LeBlanc was out the first six weeks this year with a hand injury. For us to be in a position where we qualified for the tournament, we should be very pleased,” Veneziano said.