Pagunsan, the 22-year-old son of touring pro Juanito, frolicked in the absence of winds that bedevilled the field the past two rounds to shoot one of only four under-par rounds turned in so far and inch ahead of his co-club bet Boyet Zaragosa.
Pagunsan totalled 215 while Zaragosa was right behind him at 216 after a 70 anchored on back-to-back birdies from No. 16.
Reigning national amateur champ Angelo Que was not too far behind with his even-par round marred by a double-bogey on the 14th putting him in solo third sport and very much in the hunt at 218.
Jun Jun Plana, leader in the first two rounds, struggled on the par-5s where he yielded seven strokes including a disastrous triple-bogey on No. 11. He wound up with a 78 and fell six strokes back in the fourth place at 221.
While the men’s race still looked like a four-cornered affair, Villaroman-Calimag all but settled the issue in the inaugural women’s action.
Villaroman-Calimag stole a piece of the limelight with her own under-par score, a 71, and her 144 aggregate put her 10 up on Heidi Chua who had a 76 for 154.
Lina de Guzman (78) was another five shots adrift at 159 while newly-crowned RP ladies champ Aileen Rose Yao (79-161) was virtually out of contention.