It was another heart-stopping encounter which boiled down to the final second with the Paintmasters escaping with the win as Michael Robinson missed a open jumper at the buzzer.
The Paintmasters, who took a 58-57 victory in Game One, move on the threshold of the championship with another win in Game Three Tuesday.
It appeared Shark would force a one-game standoff in the series when Chester Tolomia sank two charities off a foul by Manalo, giving the Power Boosters a 79-78 lead with 10.2 ticks left in the clock and the Paintmasters having used up their timeouts.
But Welcoat showed grace under pressure with Ren-ren Ritualo bringing the ball down court and setting up Manalo for that winning drive from the left flank.
Welcoat blew a chance to seal the victory earlier as pointguard Celino Cruz committed an error which Tolomia parlayed into two charities that gave them back in the lead, 78-77.
Shark controlled the tempo of the game at the start, taking an 18-15 lead in the first quarter before sitting on a 44-38 cushion at halftime. — Joey Villar