NORTHFIELD — The time may come when Pioneer finds itself in a life-or-death struggle on its path through the Division 5 state basketball tournament, but the first two rounds haven't yet presented any such obstacles for the unbeaten and top-seeded Panthers.

Brayden Thayer knocked down six of his team's 10 3-pointers, five coming in the third quarter alone, en route to a game-high 23 points in the Panthers' 75-43 conquest of Old Colony Tuesday night at Messer Gymnasium.

Pioneer (23-0) will host a Division 5 state quarterfinal at a time still to be determined, facing the winner of Wednesday's Round of 16 game in Boston between No. 8 seed Fenway and ninth-seeded Ware.

Kurt Redeker added 19 points and Alex McClelland scored 18 for the Panthers. They were fairly business-like in running up leads of 17-9 after one quarter and 33-16 at the half, but then avalanched on the Cougars with a 27-11 third-quarter advantage, good for a 60-27 lead entering the last eight minutes.

“It's about surviving and advancing, and one point is as good as 100,” said Pioneer coach Scott Thayer. “Sometimes we worry about the style points with a big lead. That's when we have to focus on what we do well. We weren't great in the first half, but you look up and you've given up 16 points ... As the game went on, we played more calm, more free and easy."

Pioneer entered Tuesday averaging 70.4 points per game and letting up 39.7 on average, with its closest games of the season a pair of eight-pointers, back-to-back in late December, against Greenfield and Hoosac Valley.

Old Colony of Rochester, just north of New Bedford, finished its year 21-3 after winning a second straight Small Vocational Schools state championship. The Cougars pulled the 17th seed in the Division 5 bracket.

Landon Hunter's 3-pointer 2 1/2 minutes in gave the visitors their last lead of the night at 5-4, but Redeker drove in for a layup and Jackson Glazier (seven points) bottomed out a 3-pointer to get Pioneer started on a 13-2 run and a 17-7 lead. Wyatt Smiley then beat the buzzer with a basket to get Old Colony back to within 17-9.

Smiley hit from deep again to begin the second quarter, but McClelland answered with his own trey and Glazier scored off a Ben Werner feed to make it 22-12 and force an Old Colony timeout. Pioneer slowly extended the lead, allowing only one field goal over a stretch of six minutes. Judah Glenn finished the half with an offensive rebound basket at the 0.8-second mark, after a discussion about a possible shot-clock violation by Pioneer that came to nothing.

Brayden Thayer then used the third quarter as his own personal showcase, with five 3-pointers from seemingly increasing distance. Redeker capped an 11-0 run with a two-handed dunk off a steal to make it 48-20 with 3:56 to go. Will Glazier hit a late three out of the right corner while taking a knock to the head, converting the free throw for a rare four-point play, and Thayer finished things off with a trey with two seconds left, good for a 60-27 advantage.

Smiley topped the Cougars with 13 points, while Hunter finished with nine, Nick Fringuelli eight and Aiden Deree seven.