MSEI were in a chase in payoff period as JRE led by seven points before MSEI's Bebot Ancot tied the count at 73-all to close the regulation period.
Jimlyn Campomanes put up an end-game onslaught by hitting eight of his 27 points in the extension period while Rick Annckerman, Stephen Postero and Ancot posted 16, 15, and 14 points, respectively.
In the other game, Philips, skippered by Bords Basalo, controlled the tempo in the entire game as they stunned erstwhile undefeated H20.
H2O's Boy Samson tried to revive his team by hitting four triples, however, his effort was readily answered by Rene Escuyos.
Escuyos top scored for Philips with 27 points while Audie Medina added 18 markers.
Paul Abais, on the other hand, led the losing team with 26 points while Bong Loquias chipped in 20 points.
The scores
First game
MSEI (85) - Campomanes 27, Anckermann 16, Postero 15, Ancot 14, Rosales 9, Java 2, Santos 2
JRE (84) - Delfina 18, Ortiz 18, Lareta 14, Gabutab 13, Uy 13, Tojoy 4, Zabate 4
Second game
Philips (86) - Escuyos 27, Medina 18, Divinagracia 10, Jumao-as 9, Basalo 8, Rivera 8, Cartilla 4, Ancot 2
H20 (81) - Abais 26, Loquias 20, Samson 12, de los Angeles 9, Duran 8, Padriga 4, Marte 2