SOUTH PORTLAND — They came with homemade T-shirts, a team mantra celebrated in song and a stuffed giraffe named Gerald.

They left with a sportsmanship banner and the Class A tennis state championship.

The first was a surprise. The second, not so much.

The Kennebunk girls tied a bow on their perfect season Saturday afternoon at South Portland High with a 5-0 shutout against defending champion Brunswick.

“It’s a really special thing for a group of girls to come together, who love being around each other and love playing tennis,” said Rams Coach Jacqui Holmes. “If they’re having fun out there, the rest just falls into place.”

The Class B finals also saw a champion dethroned, as Lincoln Academy knocked off Waterville, 4-1. In Class C, Washington Academy edged Waynflete, 3-2, for Northern Maine’s only tennis championship Saturday among boys or girls.

Washington Academy (14-2) of East Machias was making its first appearance in the state finals and started off in a 1-0 hole because senior Tina Pham, one of three international students in the lineup, returned to Vietnam after delivering the crucial victory in a 3-2 decision in the regional finals.

Because Washington didn’t have a replacement for Pham, Waynflete won No. 3 singles in a walkover. The Flyers also earned a point at second doubles from Anna Farmer and Jenny Morrill, 6-1, 6-2.

Washington won the rest. Yagmur Bolukbasi (of Turkey) and Crystalann Kloeber won 6-4, 6-3 at first doubles. Carlota Echevercibar (Spain) won 6-0, 7-5 at No. 2 singles, and junior Sarah Moulton capped the comeback with a 6-4, 6-3 victory at No. 1 singles in a match that didn’t end until 8 p.m.

In Class A, Kennebunk swept through the singles matches. Freshman Olivia Cutone beat MPA singles finalist Coco Meserve, 6-1, 6-0. Senior Sadie Yentsch won 6-0, 6-0 at No. 2  and junior Andie Lamontagne won 6-1, 6-3.

“It feels amazing,” said Yentsch, who explained the team motto of “Own It” thusly: “We’re present in the moment and own the moment. We have confidence in ourselves and our teammates and it led us to success.”

All four Kennebunk doubles players are seniors who took up tennis when they entered high school. Arija Grant and Hazel McEnaney won 7-6 (5), 6-4 at first doubles, and identical twin Audrey McEnaney and Ainsley Morrison won 6-2, 6-3 at No. 2.

Before playing, the girls received an unexpected gift in the form of the regional sportsmanship banner, as voted by coaches in Southern Maine. After circling up for a group hug, the girls sang to “Bad Romance” by Lady Gaga but changed the lyrics to ‘Rah-rah, rah-rah-rah, Kenn-e-bunk tennis’ capped by a spirited ‘Own It!’

“We’re always trying to be as nice as we can to people we play,” Grant said. “For us, it’s always about having fun.”

Rainy weather forced the team to cancel a practice on Thursday. Instead, they gathered in the school gym and decorated T-shirts with the names of team members, uplifting slogans and artwork.

Cutone colored a giraffe on her shirt. She had promised to bring her large stuffed mascot to the match if Kennebunk reached the state finals. It seemed a fitting end to a season she almost chose to bypass in order to concentrate on her individual development.

“I ended up signing up on the last day,” she said. “I was really not planning on playing this year.”

On Saturday, she and Gerald seemed delighted with her decision to compete for her high school team.

“She’s very grounded,” said Hazel McEnaney. “She doesn’t think of herself as being better than us. She likes to laugh and have fun and she’s like the nicest person on earth. So it’s been fun having her on our team.”

In Class B, Lincoln Academy knocked off defending state champion Waterville by a score of 4-1.

Junior Olivia Nixon (6-0, 6-1) and sophomore Laura Mueller (6-4, 6-4) won for Lincoln in the top two singles spots. Isobel Peterson and London Hunter (at first doubles) and Clare Colburn and Olive Siegel (at second) won by identical scores of 6-2, 6-1.

Waterville’s point came when senior Emily Campbell won a 10-6 tiebreaker in lieu of a third set against Vittoria Pauro after they split the first sets 6-4, 4-6.

The Eagles (16-0) completed a perfect season despite losing a dominant singles player, Caitlin Cass, to graduation last spring. Coach Melissa Burroughs said the unexpected arrival of two international students (Mueller is from Germany and Pauro from Italy) was helpful, but more important was the depth developed from a free local junior tennis program at the YMCA in Damariscotta.

“That’s the theme of the year,” Burroughs said. “As much I’m happy to have the two international players, it’s really the other seven that create that rounded team dimension. Six of our girls grew up in that (Central Lincoln YMCA) program.”