The Red Lions forced the Knights to miss 39 of their 62 attempts, including 16 from behind the arc for the decisive victory that gave them a share of the lead before the biggest roaring crowd in the season.
San Beda also limited Letran to just five free throws en route to posting its sixth win against a loss to tie its victim at the helm.
Of the five Letran free throws, Bryan Faundo went to the line thrice, making only one while Andro Quinday muffed his two foul shots.
San Beda also held pro-bound Boyet Bautista and Aaron Aban to just eight points apiece, a far cry from their averages of 18 and 12 points, respectively, with Bautista, who came into the game with 23 three-point average, failing to sink even one in eight tries.
"Boyet and Aaron are PBA potentials and are ready to play the next level so I told my players it’s a big challenge if they can limit them to a certain number of points," said San Beda coach Koy Banal.
"I’m glad the players responded," he added.
What made the win sweeter was the fact that the Red Lions did it practically minus the offensive game of the Nigerian behemoth Samuel Ekwe.
The 6-foot-8 Ekwe, the frontrunner in the MVP derby, went into foul trouble early and had to sit out majority of the game. He finished with just five points, including a thunderous slam that sent the red-clad San Beda crowd, led by its president Fr. Anscar Chopungco, OSB, in frenzy.
But Yousif Aljamal was his usual fiery self, exploding for 22 points, a point shy of his 23-point production in San Beda’s win over Perpetual Help, 61-45, last week.
"He kept assuring me that he’s going to take care of things, and he did," said Banal of his 6-foot-3 Aljamal, who last played in the PBL for Rain or Shine.
Earlier, Mapua drew a 23-point performance from Sean Co as it repulsed Jose Rizal, 64-59, to finish the first round of elimination in the magic four with a 4-3 slate.
It was the Bombers’ sixth loss against a win.