Like a raging bull, Franco, who further honed his skills playing for ICTSI La Salle in the PBL, erupted for 27 points, including six in the final period when the Dolphins weathered oft-repeated rallies by the Cardinals.
Its eighth win in 12 outings booked PCU a seat in the next round along with defending San Sebastian and St. Benilde even if the Dolphins end up tied with either Jose Rizal University or Letran at the end of the elims due to the winner-over-the-other rule.
Mapua kissed its Final Four bid goodbye after absorbing its seventh defeat against five triumphs.
The win thus left the Bombers (7-4), last years losing finalists, and the Knights (5-6) scrambling for the last semifinal berth.
"We wanted this victory so badly because it did not only clinch us a Final Four berth but it also gave us a chance to fight for a twice-to-beat advantage," said PCU coach Jimmy Mariano.
With two of the three suspended playersAlwyn Ilagan and Robert Sanzback in harness, the Dolphins strung up a series of runs connecting the first and second quarters that had them leading by as many as 16 points, 43-27.
But things changed when rookie Joeferson Gonzales and Erwin Sta. Maria teamed up in a pair of blistering rallies as the Cardinals, who played without injured starting forward Edsel Feliciano, leveled the count at 66.
Lot Soriano drained a triple to cap a 9-4 exchange that closed the third period with the Dolphins back in front, 75-70, before Franco asserted all his might in the shaded area to knock the Cardinals out.
Ilagan, Sanz and Nelson Gatdula, who did not play because of a broken right ring finger, have served the three-game suspension slapped on them for directly figuring in a brawl with San Bedas Erl Merelos during their match last month.
Meanwhile Jam Alfad struck for eight of his 16 points in the homestretch as reigning titlist San Sebastian downed San Beda, 87-85, to seize the solo lead with a 10-9 record. It was the Lions 11th setback against a win.
In the juniors division, San Beda ripped San Sebastian, 76-66, while Mapua crushed PCU, 82-57.