Biddeford's Ayla Lagasse celebrates after cutting down the nets following the Tigers' win over Oceanside in the Class B South final. Derek Davis/Portland Press Herald

The Biddeford girls basketball team’s grip on its first trip to a state championship game was suddenly shaky. The Tigers had a four-point lead over Oceanside midway through the third quarter, but tone-setter Jordyn Crump was on the bench because of foul trouble.

“I was like ‘We have to do something to calm ourselves down, and realize it’s going to be OK,'” freshman guard Gabriella Silva said.

Fourteen straight points served that objective well, as No. 4 Biddeford went on a game-deciding run that helped salt away a 62-38 victory over defending state champion and No. 3 seed Oceanside in the Class B South final Friday at the Portland Expo.

Ayla Lagasse scored 15 points while Silva added 13 and Crump had 10 for Biddeford (16-5), which last won a regional title in 1974, the year before the first official girls state tournament.

“It’s an unreal feeling,” said Silva, who added 11 rebounds and five steals and was named the tournament’s most outstanding player. “To win and go to the state championship when it’s really never been by Biddeford before, it’s an incredible feeling. It’s so surreal.”

Aubri Hoose scored 15 points and Renee Ripley and Abby Stackpole added nine apiece for the Mariners (15-6), who fell just shy of a third regional title in four years, even after star Bailey Breen transferred to Florida prep power Montverde Academy before the season.

“I sat the seniors down and I told them, ‘Look, usually at the beginning of every year we’ve got every newspaper wanting to talk to us. This year, it’s a ghost town,'” Oceanside coach Matt Breen said. “I said ‘No one gave you the opportunity, at best they thought you’d make it to a prelim. And you proved them all wrong.'”

Showcasing a tenacious defense and skill in transition, Biddeford jumped out to a 27-19 halftime lead, led by nine points from Lagasse and six from Crump. But with 5:01 left in the third and the Tigers ahead 30-24, Crump, the team’s top ball-handler and floor leader, sat after picking up her fourth foul. When Hoose made two free throws seconds later, it appeared the door was open for the defending champs.

“It could have gone either way,” Lagasse said, “but we stay focused, we know (it’s) one play at a time. If we mess up, it’s the next play.”

If the door had opened, Biddeford slammed it shut. Anna Smyth made a basket on the next possession, and after two misses, the Tigers hit their final six shots of the quarter. Lagasse sank a jumper, Natalia Silva (nine points) made a runner, and another Lagasse basket prompted an Oceanside timeout at 38-26.

It didn’t work. The Tigers drained 3-pointers on their final three possessions, one by Natalia Silva and the other two by her twin sister, for a 47-29 lead going into the fourth.

In all, Biddeford made 13 of its next 16 shots after Crump left the court, turning a tight game into a runaway.

“At the end of the day, these kids play for one another,” Biddeford coach Jeannine Paradis said. “When one kid is down, someone lifts us up.”

On Friday, that was Lagasse, who scored eight points in earlier playoff victories over Wells and Spruce Mountain but played a starring role against the Mariners.

“I don’t really look for my shot. I let it come to me,” Lagasse said. “I try to cut as much as I can, and when they find me, they find me.”

Biddeford went 0-18 two seasons ago, capping a stretch of poor records that resulted in the program dropping to Class B last season via the reclassification rule that debuted that year. But with an incoming class of freshmen, including both Silvas and starting guard Mia Mariello, that won three straight New England championships in middle school, all eyes were on the Tigers entering this winter.

“At the end of the day, these kids know that they’re good, and we’ve had the community support behind us,” Paradis said. “But with that comes feeling the pressure as well, knowing there are certain expectations. … They just came out and played with grit, composure, like a veteran team.”

Breen said he wasn’t bothered by Biddeford, of Class A-sized enrollment, playing in B.

“It’s not like they went outside the rules, that’s where they were placed,” he said. “I didn’t have a problem playing them last year when we won (in the quarterfinals), so I’m not going to have a problem playing them this year when we lost. They’re a great team, they outplayed us.”

Not before the Mariners, with 10 players in the entire program, made a run no one saw coming.

“They came together, Aubri grew up in front of your eyes and became an amazing leader, other girls stepped up,” he said. “It’s been a hell of a season for us.”