By Ayoub Kourikchi, Globe Correspondent

The St. Mary’s boys’ basketball team erupted for 60 second-half points, erasing a 17-point halftime deficit (35-18) to sink host Arlington Catholic, 78-63, and take over first place in the Catholic Central Large Monday night.

St. Mary’s (13-3, 7-1) was led by senior captain Nick Gagliolo, who netted 20 of his game-high 29 points in the second half. The talented 6-foot-1 guard also scored his 1,000th career point, in dramatic fashion, drilling a third-quarter buzzer beater on a fallaway jumper in the lane to even the game at 46-all.

“Nick is a three-year starter and it’s a luxury as a coach to have a player like this at this level. He is a leader and has all of the intangibles that make him a special player,” said St. Mary’s coach Kevin Moran. “After he scored his 1,000th point he turned around and said, "Let's take of business and see if we can finish.”

The Spartans matched Gagliolo’s intensity throughout the second half and exploded with 28 third-quarter points after they struggled in the first 16 minutes.

“The match was clearly a game of two halves," said Moran. "We took too many 3-pointers and we didn’t get any offensive rebounds and we didn’t execute offensively in the first half.

“I expected them to go out in the second half with more intensity and they took it upon themselves and convinced each other to start compete at a high level.”

The Spartan’s carried their momentum into the fourth quarter where they outscored the Cougars (10-3, 6-2), 32-17.

“We got the ball moving and a lot of our points came off transition,” said Moran. “Our defensive pressure got better. We stayed in man-to-man defense, and we were more aggressive and we rotated and defended them much better and that created a lot of our offense and it helped us push the ball up and get better looks.”

Senior captain and guard Devin Thomas finished with 15 points and sophomore point guard Randolph Thurman collected 9 points, 9 assists, and 7 steals.

“The kids knocked down the shots and they ran the show tonight and they picked up the momentum,” said Moran.

“I have been coaching at St. Mary’s for eight years and [the team has] never scored 60 in a half and all things considering it’s probably one of the best games we have played in a long time.”