AUGUSTA — Milo Belleau had the basketball in the open court and no one between him and the rim Monday.

He hesitated, took another look behind him and turned on the jets, sprinting in for a left-handed dunk that provided the finishing touch to Waynflete’s 54-40 victory over Hall-Dale in a Western Class C quarterfinal at the Augusta Civic Center.

“Coach (Rich Henry) probably didn’t approve of it,” the Flyers’ junior guard said. “I was thinking about it and we weren’t up by that much, and when am I going to be wide open again?”

Belleau hit for a game-high 20 points to help third-seeded Waynflete (16-1) pull away. He scored eight of his team’s 10 points in the third quarter, including a pair of 3-pointers from well beyond the arc.

In the first quarter, Belleau kept driving to the basket, being jostled by Bulldog defenders and missing his shots. He had to adjust to the more lenient officiating that the postseason brings. In the second quarter, Belleau drifted outside for a 3-pointer and a baseline jumper as the Flyers grabbed a 25-22 halftime lead.

“They were giving me the shot more than attacking to the hoop,” Belleau said. “I kind of adjusted to that, realized they were giving me the 3. I’m pretty confident with my shot overall.”

Hall-Dale (13-7), the sixth seed, kept the score close by descending on the offensive glass, grabbing rebounds and forcing fouls. The Bulldogs got 10 of their 22 first-half points at the free-throw line, but none in the second half.

Waynflete did a better job of controlling the boards, which allowed the Flyers to get into transition and build a 44-36 lead.

Then the Flyers began stalling to protect that advantage. Hall-Dale was forced to foul. Waynflete went 8 of 10 from the foul line before Belleau’s dunk.

“We just wanted to stay down on defense and definitely limit their possessions,” said Waynflete senior guard Harry Baker-Connick, who added 12 points and made all four of his free throws down the stretch. “We just didn’t really play our game in the first half. I try to set up my teammates first. Things weren’t falling so I decided to attack a little more than I usually would.”

The Flyers used a 2-3 zone to try to clog up the lane, letting Hall-Dale shoot open 3-pointers. The Bulldogs made only two, both by Quinn Stebbins in the second quarter.

“We try to play as active as possible in our zone,” Henry said. “We felt like if we had to give something up, as aggressive as they are on the glass, we were going to give up the 3-point shot.”

Waynflete faces Dirigo in the semifinals at 7 p.m. Thursday.