FALMOUTH — This postseason, the longtime Class B Yachtsmen are off to the uncharted waters of the Western Class A state tournament.

So far it’s smooth sailing.

Elle Fitzgerald scored two second-half goals Wednesday night to lead Falmouth to a 4-0 victory over Sanford in a field hockey quarterfinal at Falmouth High.

The third-seeded Yachtsmen (13-2) advanced to a regional semifinal Saturday against No. 2 Massabesic (13-2) in Waterboro. The Mustangs advanced with a 1-0 quarterfinal win over No. 11 Westbrook (9-7) earlier Wednesday. Sanford finished at 8-8.

Also unfamiliar territory for Falmouth: a few-goal cushion. Strong defending has made up for a general lack of scoring this season; the Yachtsmen won 5 of 6 one-goal games and posted 11 shutouts.

“Those taught us we can never let up,” Mikey Richards of Falmouth said. “You have to be on, you have to be ready. They really prepared us for the playoffs.”

Even the Class A playoffs, where Falmouth will face largely unknown opponents after playing a Class B schedule in the regular season.

“You can really get hyped up about not knowing their (game); we focused on our (game),” said Falmouth Coach Robin Haley, “and it paid off. This game gives us some confidence. We just want to play well.”

And it did, particularly in the midfield. Dayna Vasconcelos, Sydney Bell and Kate Lannon were strong, helping to keep Sanford away from goalie Hillary Nash (two saves).

“We focused on getting back on those defensive free hits, gaining possession and passing the ball,” Haley said. We did that for the majority of the game and that made the difference.”

Richards got Falmouth rolling, redirecting a long pass from Leika Scott past Sanford starting goalie Sarah Goldthwaite (six saves) with 8:32 left in the first half. (Backup keeper Teaghan McCormack, who came on with 20 minutes left in the game, made two saves.)

Scott started the play that led to Falmouth’s second goal about five minutes into the second half. She knocked the ball in from the right wing. It bounced around at the goalmouth before Fitzgerald poked it in for a 2-0 lead.

About six minutes later, Tallyn Brown broke in for what looked like Sanford’s best chance of the night. But defender Hayley Winslow rode her across the crease without a shot.

Winslow set up Falmouth’s third goal with 10 minutes to play, stripping a Sanford forward of the ball, carrying up field 20 yards before sending a through ball to Fitzgerald, who cracked it in from 15 yards.

“I had a little time and got a bit of a windup,” she said. “And it went by the right side of the goalie.”

Three minutes later, Bell made it 4-0 by finishing off a scrum created by the high pressure of Kristen Coleman and Fitzgerald.

Despite the loss, Sanford Coach Diane Walker was upbeat. Including the playoffs, the Spartans won five of their final seven games.

“I’m proud of them. With all the injuries we’ve had, we really showed a lot of improvement as the season went on,” Walker said. “The seniors stuck with these young kids, worked with them all season long to get to this point. No one expected us to get this far. We never gave up.”