Northport's Luke Petrasek, right, gets a congratulatory pat from teammate...

Northport's Luke Petrasek, right, gets a congratulatory pat from teammate #21 Austin Marchese after blocking a shot in the fourth quarter of a game against Central Islip. (Feb. 1, 2013) Credit: James Escher

An alley-oop blew the roof off a full house, but a Northport victory was built block by block. And shot by shot, too.

Luke Petrasek hauled in a perfectly tossed lob from Matt Smith for a resounding dunk that helped build a 15-point fourth-quarter lead and the host Tigers won the battle for first place in Suffolk League II with a 58-53 victory over Central Islip before an overflow crowd Friday night.

They sat in the aisles and stood in the doorways to watch the 6-9 Petrasek post a triple double -- 20 points, 12 rebounds and 10 blocks -- and Mike Milligan score nine of his 19 points in a game-turning third quarter in which Northport (15-1, 9-1) made six three-pointers.

"They were collapsing on Luke and that left me wide open," said Milligan, who made three shots from downtown in the third, when Northport outscored CI 22-8. "I know we are a great three-point shooting team. We just had to relax."

That's not easy to do against the Musketeers' vaunted 2-3 zone and all-court trap. But Smith, the Tigers' point guard, played a strong game, with 13 assists and just two turnovers.

Petrasek blocked four shots in the third quarter, making it tough for CI (14-3, 9-2) to get to the rim. "We're like brothers. We have a little sibling rivalry going on with the blocked shots," said Milligan, who had four blocks and eight boards.

Petrasek was not only an inside force, but he helped spread the floor by sinking three treys. "I love shooting the three," Petrasek said. "People underestimate my shot."

Northport, a title contender in Class AA, lost its only game to CI, 53-52, on Jan. 8. And when the Musketeers scored the game's first nine points and led 12-4 after the first quarter, it didn't look like this one would be that close.

Turns out it wasn't, but it was CI doing the chasing. Tim McKenzie scored seven of his 23 points in the final minute to make the final score respectable, but the outcome was never in doubt once Petrasek slammed on offense and slammed the door on defense. "I like blocking shots, too," Petrasek said.