WATERTOWN – As the calendar turned to 2024, the Belmont/Watertown Girls’ Ice Hockey team faced a gauntlet: Five games in 10 days from Jan. 4-13, primarily against Middlesex League opponents. It was a big test for the new co-op team under first-year head coach Brendan Kelleher, which had started with a promising 2-0-1 record.

Four wins and one tie later, the Marauders were on their way to a historic season, which led to winning the Middlesex League and being the last undefeated team in the state this season after starting 10-0-3.

“That was really a big stretch, and to come out of that unscathed, if you will, it was pretty impressive,” Kelleher said. “Heading into that week, it was a little [like] ‘What do we have here?’ And then you come out of that with [four] wins and a tie, which was the turning point, I think for me and all the coaches and the team, to see we got a pretty solid group here.”

Now, No. 14-seeded Belmont/Watertown (13-2-3) hopes to make a run in the Division 1 State Tournament, starting with a first-round matchup against No. 19 Billerica (6-9-5) on Feb. 29.

The first year of these two former Middlesex League rivals uniting on one team has brought out the best of both sides. The team has just three Watertown players out of 21 on the roster, but two serve as captains: Molly Driscoll scored more than half the team’s goals (21), and Aislin Devaney is one of the leading defenders.

On the Belmont side, co-captain Lola Rocci leads the team with 10 assists and sophomore goalie Jil Costa posted nine shutouts, but the group no longer views itself as a Belmont/Watertown hybrid; it’s simply one team.

“The only way you know who the Watertown players are is they have black helmets, and the Belmont players have white helmets. That’s it,” Kelleher said. “Once that puck drops, we’re all one big team and one big family, and it’s been nice to see the girls get to know each other on and off the ice, which has been great.”

Kelleher, who took over the program after ending a 21-year run as an official in the NCAA’s Hockey East, wanted to prioritize a positive experience for his team. His daughter, Devin, graduated from Belmont last year, and he taught many of the current players how to skate in their youth days through the Mini Marauders program.

That familiarity with the group and an environment that balances hard work with having fun made it easy for the players to buy in.

“Practices are always very fun,” senior co-captain Gretchen Hanley said. “He (Kelleher) tells us what we’re doing wrong, but definitely tells us how to fix it, so this year has been a very positive environment.”

The Marauders rattled off wins by laying a tight, defensive game. They allowed just 15 goals over the entire season – the fewest in Division 1 – but were bottom 10 in goals scored with 39. Their regular season ended with a 1-0 overtime loss to Waltham, which served as a wake-up call.

“We really just have to push ourselves to get in the mindset that it’s playoff time now,” Rocci said. “And playing that game as a 1-0 game in overtime, that’s what we could see during playoffs. We have to get stuff done, sooner and faster, and with that energy coming out of that game, putting it into the first period of the first playoff game.”

Kelleher said he never feels comfortable in the close games his team has played, despite winning most of them, but he recognizes the experience in those situations should serve them well in the state tournament. After Belmont/Watertown answered its first loss of the season – 2-0 to Burlington on Feb. 8 – with a 3-1 win against Arlington two days later, Kelleher trusts the bounce-back ability of the team.

Now in “survive-and-advance” mode, Belmont/Watertown is just focusing on what it can control. Against Billerica, they’ll rely on Costa and the defense to shut things down like they have all season. When it comes to expectations for the first round and beyond, the players are keeping it simple.

“Expectations are we just do the same thing we’ve been doing,” Devaney said. “Working hard, showing up, putting in the time, giving it 100 percent. … It’s just kind of like any game. Stakes are a little bit higher, but going into each game, do your job.”

For the Marauders, the job began Thursday with a 1-0, double-overtime win over Billerica/Chelmsford. Next up: Lincoln-Sudbury.