The win improved the Cardinals’ record to 7-4 win-loss card for a firm grip at third place, virtually giving defending champion Philippine Christian U Dolphins (8-2) a free ride to the semifinal round.
League leader Letran Knights, still unbeaten in 10 matches, were the first to barge into the crucial phase of the tournament.
On the other hand, it was the second straight loss for the Red Lions as they moved on the brink of elimination at seventh spot with a 3-8.
"I really have to give credit to the boys," said Mapua coach Horacio Lim. "It still boils down to a win. Maybe we can still catch up with PCU at the No. 2 spot and possibly earning twice-to-beat advantage."
In the second game, San Sebastian College likewise boosted its own semis bid with a 65-60 win over Jose Rizal U for its sixth win against five losses. The Bombers bowed out of the race with a 2-9 card.
Red Vicente fired 20 points and Leo Najorda, who was selected sixth overall by the Red Bull Barako in last Sunday’s 2005 PBA Rookie Draft, scored 10 of his 19 points in the pivotal third quarter to power the Stags to victory.