The first half of Saturday’s lacrosse game between Brunswick School and Deerfield Academy saw the Bruins register an impressive 13 goals, yet the visitors from Massachusetts were still within striking distance, behind a nine-goal opening half.

However, much to the Bruins delight, the scenario quickly changed.

Limiting Deerfield to just one second-half goal, Brunswick pulled away from their New England West Division I rival, earning a decisive 21-10 victory before a large crowd at sunny Cosby Field.

With the win, the Bruins, ranked No. 1 in the Nike/USA Lacrosse Top 25 List and the Inside Lacrosse Top 25 Power Rankings, raised their record to 3-0.

Senior midfielder/tri-captain Tomas Delgado recorded four goals and three assists, while junior attack Payton Anderson notched three goals and two assists to pace Brunswick in its latest triumph.

The Brunswick-Deerfield rivalry has been back-and-forth, with both teams having their moments the past decade.

“It’s always a fight when we go against Deerfield,” Delgado said. “The last 10 years, we have a record of 5-5 against them. Going into this game we knew it was going to be a tough one. We had to play 48 minutes.”

Senior Jackson Wolfram recorded a hat trick with one assist for the Bruins, who received two goals and three assists from senior midfielder Leo Hoffman. Brunswick led 8-4 after the first quarter, then headed into halftime with a 13-9 advantage on Deerfield.

“They couldn’t stop our offense,” said Wolfram, who will play lacrosse at Brown University next year. “Twenty one goals, you can’t really ask for more. We had a variety of scoring threats, so it was a great showing by our offense.”

Junior goalie Tucker Williams made nine saves for the Bruins, who saw senior Notre Dame-bound Andrew Greenspan win an eye-opening 34 of the 39 faceoffs he took.

“Offensively, we were clicking from the start,” Brunswick coach David Bruce said. “Greenspan at the faceoff X was high 80 percent (87 percent) and he scored two goals while doing that. It relieves a lot of pressure in the middle of the field when you win faceoffs and score a goal and you get the ball back.”

Trailing 13-9, Deerfield closed to within three goals of the Bruins when senior Owen Bunten scored at the 9:36 mark of the third quarter. That proved to be the visitors’ final goal against the Bruins, who broke the game open from there.

Junior attackman Max Warden scored with 3:16 remaining in the third quarter, then Greenspan won the ensuing faceoff, took it down the field himself and tallied six seconds later, making it 15-10. Consecutive goals from Anderson made it 17-10 in Brunswick’s favor with 13.2 seconds to go in the third quarter.

In the fourth quarter, Hoffman converted a shot from 10 yards out and Wolfram added a tally in the final quarter to help seal an outstanding offensive game by the home team.

“It’s a big rivalry,” said Hoffman, who will play at the University of Pennsylvania next season. “The seniors, juniors and sophomores know this has been going on for years. It was a back-and-forth game, they never went away. I’m proud of the offense, defense, our goalie and our faceoff guy – all around I was super impressed with everybody.”

Greenspan scored after winning a faceoff, putting the Bruins on top of Deerfield, 8-4, going into the second quarter. The Big Green cut Brunswick’s lead to 8-6 with two straight goals, one of which was scored by Bunten. Delgado scored off a pass from senior defender/tri-captain Hunter Spiess and Anderson set Wolfram up for a goal, making it 10-6. Senior midfielder Patrick Mullen added a goal off a laser from 12 yards out with 7:03 to go in the second frame, giving the Bruins an 11-7 edge.

“It was awesome, everybody was getting their stuff going,” Hoffman said. “It wasn’t a one-man show, we were moving the ball well. They started off in a zone, which we weren’t expecting. But they came out of there quick, when we set up our offense.”

In the second half, the Bruins limited Deerfield’s scoring chances and had the advantage in possession time.

“I think we were over aggressive defensively in the first half,” Bruce noted. “We were making mistakes that we typically don’t make. Deerfield is too talented to exploit those mistakes and they did. In the second half, we played really well.”

Said Spiess: “Obviously, the first half we came out a little slow. We had some things to work, but we regrouped in the locker room and I thought we were a lot more solid in the second half. We talked about playing aggressive defensively.”

The Princeton-bound Spiess had one goal and one assist, while Warden, senior midfielder Will Erdmann, Mullen and junior midfielder Kyle Pagnani added one goal apiece in the winning effort.

“It’s always a good day when you score 21 points,” said Delgado, who will take his lacrosse skills to Duke. Delgado has impressed with his on-target shooting ability.

“I feel we have the best step-down shooter in Tomas Delgado in the country,” Hoffman noted. “It’s pretty easy when he gets the ball from 12 yards.”

“It was a total team effort,” Hoffman continued. “Andrew Greenspan was tremendous. Goalie Tucker Williams was awesome, our 1-on-1 defense got better as the game went on. I am so proud of the defense for picking it up in the second half.”

The Bruins have a busy week ahead of them, with three road games. They will visit Kent School on Wednesday, travel to Darien on Thursday in an intriguing non-conference matchup, then go to Loomis Chaffee School on Saturday.

“Darien is always a really fun one, we have a big rivalry between towns, Greenwich and Darien,” Wolfram said. “It’s at Darien, so it should be a fun, competitive, physical game. To have this win on Cosby our senior year against Deerfield feels good.”