Warren Bonifacio powered the Cardinals with 14 points, nine rebounds, and three assists as they won their fourth game in five outings.
Jeric Pido added 13 points and four boards, Paolo Hernandez went for 11 points, five assists, and two steals, and Toby Agustin had 10 for Mapua which climbed up to a 4-9 card.
The Cardinals unleashed a 26-point third quarter to take a 60-54 advantage heading into the payoff period, while also surviving a hot night from Carlo Ferreras, who had 18 of his 22 points in the second half.
With Mapua taking a 10-point lead, 69-59, with four minutes left to play, Perpetual refused to quit and got to within four, 69-65, but got its air knocked off after Jielo Razon's costly turnover which led to Adrian Nocum sealing the game with two freebies in the last 11.9 ticks.
Ferreras shot 4-of-5 from deep, to go with his four rebounds and four assists for the Altas, which slid to a 5-7 record.
Christian Pagaran had 10 points and three rebounds as JC Abis had five points, eight boards, three steals, and two blocks for the Altas.
Mapua 73 - Bonifacio 14, Pido 13, Hernandez 11, Agustin 10, Nocum 9, Cuenco 8, Mercado 6, Soriano 2, Garcia 0, Salenga 0.
Perpetual 65 - Ferreras 22, Pagaran 10, Abis 5, Egan 5, Roque 5, Boral 5, Barcuma 4, Flores 3, Razon 2, Omega 2, Nitura 2, Martel 0, Orgo 0.
Quarterscores: 18-23; 34-37; 60-54; 73-65.