“I started playing at the end of eighth grade,’’ said Donahue, who is following in the footsteps of her older sister, Ann, as captain of the Wamps this season.

“My sister Ann started playing in high school and thought it was really fun so I started playing.’’

By her sophomore year, she had earned a spot on the varsity. And her younger sister, Nora, now a sophomore at Braintree, also plays volleyball.

“Ann definitely got me into the sport,’’ said Donahue, an outside hitter/middle blocker. In the offseason, all three sisters play for the Mass Patriots, a Junior Olympic team based out of North Quincy.

Ann, now a freshman on the women’s team at Assumption College, was a dominant player in the Bay State Conference last season, setting a program record for kills (253) in a season.

This season, Mary Donahue has taken a leadership role. Her focus is rebuilding the team.

“We lost eight players, including all three middles and my sister,’’ said Donahue. “We only have three seniors, everyone on the team is young. It’s going to be tough.’’

Last season Braintree fell just short of capturing the Bay State Conference Carey crown, finishing one game in back of Newton North.

“It was close last year, but they won,’’ said Donahue. “We’re looking to get back at the top this year, but it’s going to be a challenge since we’re rebuilding.’’

Braintree coach Kristen Orzechowski said Donahue is the heart of her squad. “She’s such a hard worker,’’ said Orzechowski. “She put in all the effort in the offseason, she’s improved so much.’’ Orzechowski is also a coach with the Mass Patriots program.

Over the summer, Donahue participated in two volleyball camps (one at Bentley, along with the “I Dig It’’ program at North Quincy High) as well as playing in the Bay State Games. She was the only player from Braintree on the Southeast squad, which captured the bronze medal.

Senior captain Abby Lucas said Donahue is the best player on the team.

“Having Mary here, everyone’s able to build off her, learn from her seeing how good she is,’’ said Lucas. “She’s not very vocal, but she leads by example.’’

Lucas has known Donahue since first grade. “She’s just a great person,’’ said Lucas, “on and off the court.’’

“She is a great leader; she leads by example in everything she does,’’ said Orzechowski. “She’s always been a good hitter, but now she’s a great hitter. She’s made sure she can serve, receive, and play defense. She’s really worked hard so that she’s not a one-dimensional player.’’

And now is Donahue’s opportunity to shine.

“Her sister was our star player last year, it was a matter of time for her to take over,’’ said Orzechowski. “She’s realized it’s her season this year. She wants to star and make sure she is the best player on the court.’’

Orzechowski, who started coaching when Donahue was a freshman, has watched her progress rapidly over the past three years and improve all assets of her game.

“Her sophomore year she was athletic and tall but there was a matter of getting her coordination together. Now her vertical has increased tremendously. She’s hitting at the peak. She can reach . . . almost the height of a basketball hoop.’’

Traditionally, taller girls do not play at the defense. Donahue, however, had made it a goal.

“We don’t look at 6-foot-1 players to be our defensive players,’’ said the coach. “She’s made it her challenge. She wanted it as her goal. Now she’s not just hitting and blocking. She’s hitting, blocking, serving, and playing defense.’’

Donahue is in the top 10 percent of her class and is a member of the National Honor Society and French National Honor Society.

“She’s such a smart kid. Not only is she academically intelligent, she knows what’s happening in the game,’’ said Orzechowski. “She understands what the other teams are doing and is always making adjustments.’’

Nora Donahue said she is excited to follow in her older sister’s footsteps. “She’s my sister and a good player. I look up to her as a mentor,’’ said the 6-foot sophomore. “Since we’re doing these things every day after school we’ve gotten a lot closer.’’

Nora has only praises for her sister. “She’s so good. She can hit really hard. She’s a great all-around player. We always root each other on. On the court we have our own handshake, it’s fun when we’re out there together.’’

Ann Donahue is thrilled that Mary has followed her as captain.

“It was nice to see,’’ she said. “My sisters and I are really competitive, so it’s nice to see her succeed in something I did.’’

She also thinks that Nora will follow in their footsteps. “We’ve always had the same interests in academics and sports. I can see Nora doing the same as us.’’

For now, Mary Donahue will focus on her season and then start thinking about college. “I’d like to play at a smaller Division 1 or at a Division 2 school,’’ she said.

What keeps her going, she said, is “the feeling you get after a rough practice. It’s so rewarding seeing yourself improve. I love it, and I love the team atmosphere.’’

Colleen Casey can be reached at colleen.casey@globe.com.