All of 5 feet 6, Thomas Gandolfi plays all-out, all the time, because it’s all he knows.

Which doesn’t mean Mundelein’s diminutive defender is all out of energy down the stretch in basketball games.

“I joke with my friends that I hide around the first three quarters and then just come out in the fourth,” said Gandolfi, who’s starting for the depleted Mustangs. “When I get my opportunities, I take them.”

And so he did Wednesday night.

Gandolfi hit his only two 3-point attempts in the fourth quarter, helping Mundelein pull out a 66-54 win over Barrington in third-round action of the Mundelein/Warren Thanksgiving tournament.

Mundelein improved to 2-1 in the tourney with its second straight win and will host Waukegan at 6 p.m. Friday.

Barrington (1-2), which got 15 points from Zach Bart and 13 from Raymond Tolentino, will face Lake Forest Academy at 4:30 p.m. All four tournament games Friday will be played at Mundelein.

“We got a lot of good shots tonight. The ball just didn’t go down for us,” said coach Bryan Tucker, whose Broncos made just 1 of 7 shots in the fourth quarter after the game was tied 38-38 after three. “(Mundelein) knocked down shots. The teams went toe to toe. It was pretty much an even game at half (Mundelein up 27-26) and an even game at the end of the third quarter.”

Known for his hustle plays, Gandolfi chased the ball in anticipation of a rebound after each of his high-arching 3-pointers.

“I was under the basket waiting for (the ball) before it even came through the hoop,” Gandolfi said. “Everyone teaches me to run after the ball because half of the time you’ll get it. That’s what I do. Even if I know it’s going in, I’ll do it just in case.”

Already minus three starters in Robert Knar (ACL), Nate Williams (injury) and Missouri S & T-bound Chino Ebube (disciplinary reasons), Mundelein had to win down the stretch without Sean O’Brien, whose 22 points led all scorers. The 6-7 Southern Illinois recruit was whistled for his fifth foul when Barrington’s Austin Madrzyk took a charge with 3:20 left in the fourth and Mundelein clinging to a 54-50 lead.

“Of course we were a little concerned, but we couldn’t act like that in that situation,” Gandolfi said. “We knew we had to keep our heads up, and we knew we had to have some more guys take charge and be leaders.”

Gandolfi was one Mustang who did, as his second 3 of the fourth extended Mundelein’s lead to 57-51 with 2:56 left. Cliff Dunigan (9 points) and Quinn Pokora (10 points) each sank 4 of 4 free throws in the final 2:08. Gandolfi also hit one, helping the Mustangs outscore the Broncos 12-4 after O’Brien fouled out.

“I thought (junior forward) Adam Turner did a great job coming back in, and Thomas Gandolfi hit two huge jumpers,” Mundelein coach Dick Knar said. “He’s been our energy guy and has hit some really clutch jumpers for us the last two games.”

Gandolfi scored all 7 of his points in the final quarter. Dylan Delaquila also scored in double figures for Mundelein, sinking three 3-pointers and finishing with 13 points.

Barrington star guard Brad Zaumseil injured his ankle in the first half, but got it taped and played the rest of the game. He hit 5 of 6 free throws in the fourth quarter to finish with 10 points.

“What a gutty performance from him,” Tucker said. “He was obviously in a lot of pain. He gutted it out.”

Robby Vollman had 8 points and 8 rebounds for the Broncos.