Grace O’Donnell was a wide-eyed freshman watching from the sidelines when Yarmouth won the 2011 Class B girls’ lacrosse championship.

The memory of that game tugged at her for three years.

“It was an amazing experience, just watching how all those upperclassmen played and their respect for each other,” O’Donnell said. “Their love for the game of lacrosse made me want to keep going and win as a senior, for sure.”

O’Donnell was a budding star as a sophomore and junior, but her Clippers fell in the playoffs to Freeport in 2012 and in the state title game to Waynflete the next year.

Those losses gnawed at O’Donnell. But she was also driven by a bit of insecurity.

“I had a really good season as a junior, so I was kind of worried coming into this season that I already peaked or that teams were going to really target me and I wasn’t going to be able to handle that,” she said.

She spent the summer practicing with friends, her little brother or by herself in the yard, using shirts as targets.

It certainly paid off. O’Donnell, the Maine Sunday Telegram’s Player of the Year, scored 56 goals, added 17 assists, scooped up 35 groundballs, controlled 46 draws, forced 17 turnovers and ended up hoisting a trophy.

“I could put her anywhere. That’s the best part about her. She would just go, which is huge, because she had that confidence,” said Yarmouth Coach Dorothy Holt.

“She was working on conditioning and speed and agility. She was just becoming a more confident shooter. Her shots were getting stronger and harder and sharper. We say. ‘Shoot with your bread-and-butter shot.’ But Grace didn’t have just one. If she wanted it to go in, it went in.”

O’Donnell was listed as a midfielder but spent a great deal of her time on the attack. She fired 90 shots at opposing goalkeepers. Seventy were on target, and a remarkable 80 percent of those found the back of the net.

O’Donnell will play next season at Trinity College, where she’ll be joined by Cape Elizabeth’s Abby McInerney. The two have become friends, but the Class B state championship game tested those bonds.

O’Donnell scored six goals and the Clippers built a 12-3 lead in the second half. McInerney wouldn’t let the Capers fade away so easily. She led a late charge and finished with eight goals, causing some consternation for O’Donnell and her teammates. Yarmouth held on for a 13-10 win.

“We would talk in the draw circle,” O’Donnell said. “I’d say, ‘Nice shot. Can you stop?’ She did what she had to do for her team if they were going to have any chance. I was just staring at the clock. It seemed like it was taking forever.

“We had played such a strong game that there was no way we were going to let ourselves lose. We three captains (Julia Primeau and Abby Belisle Haley were the others) said from the start that there’s no way we can lose this game. Each one of us is not going to let this team lose this game.”

O’Donnell is more than just a gifted athlete. In fact, she said she wasn’t even sure she would play lacrosse in college. She didn’t commit to Trinity until February, in the midst of her basketball season.

She is a top student and has already traveled extensively in America, the Caribbean and Europe. Her mother is from Ireland and she has visited there often. She also spent two weeks with a family in Spain and visited France. She wants to major in Spanish or biology, or both.

She took up the flute at age 5 – a neighbor was a tutor – and became so accomplished that she spent the past four years as a member of the Portland Youth Wind Ensemble.

“It helps me focus and become more organized,” O’Donnell said. “A lot of kids become really focused on their sport, but I wanted to keep music in my life, so I found a way to balance both.”

The twin passions overlapped in other ways.

“It’s hard work and practice that helps you succeed in both,” O’Donnell said. “I put a lot of effort into it and a lot of time. I’ve learned so much from both of them.

“Dealing with pressure, too. Once you make the ensemble, you usually make it again. But someone can steal your spot. You always have to play your best; you can’t take anything for granted.”

Certainly not a state championship.