University of Santo Tomas rode on its comebacking forward while De La Salle University leaned on its rookie as both teams posted thrilling victories in the third day of the 75th UAAP men's basketball tournament in front of a huge crowd at the Smart Araneta Coliseum.

Aljon Mariano shone bright in the rainy Thursday afternoon in towing the Growling Tigers to a huge upset, a 71-70 nipping of four-time defending champion Ateneo de Manila University in the first game.

Down 19 points late in the second quarter, Mariano and the Espana-based crew gradually chipped away at the Blue Eagles' lead with a third quarter for the ages.

Mariano peppered Ateneo with 13 of his game-high 21 points in the third, where UST put on a 30-point juggernaut that turned a 15-point halftime deficit to a 58-54 advantage entering the final quarter.

The Blue Eagles kept it close in the fourth quarter but other Tigers joined the attack, with Jeric Teng draining a three-pointer to extend the lead to 64-57.

Four straight points by Karim Abdul put UST comfortably up, 71-67, with 10.3 seconds left, before Ateneo point guard Juami Tiongson stopped the celebration with a running trey to trim the gap to 71-70, 4.3 ticks remaining.

However, the Eagles burned almost three seconds trying to foul a Tiger, with the referees finally blowing the whistle that led to two free throws for Teng, both of which he missed with 1.8 seconds left on the clock.

Ateneo, though, could not grab the leather and as time expired, UST players and coaches erupted in celebration at center court after beating the Eagles for the first time in 13 tries, ending a 12-game losing skid dating back to 2007.

"Siguro law of averages lang," winning coach Pido Jarencio said. "Hindi naman pwede na kami yung laging talo at naghihinagpis."

Mariano also finished with 13 rebounds even as Teng and Abdul had 16 and 14 points, respectively.

Kiefer Ravena led Ateneo with 19 points and five boards while Nico Salva chipped in with 17 markers and eight rebounds as the Eagles fell to .500 for the first time in quite some time.

Meanwhile, rookie Jeron Teng played the hero's role anew to help the Green Archers escape another upset bid, this time from the University of the East, in a 67-59 victory.

Blown out by 35 on opening day, the Red Warriors entered the game on a mission, lurking behind La Salle's back all game before a fourth-quarter spurt starring Teng doomed their hopes.

The Archers held a precarious 51-50 advantage midway through the fourth after a third-quarter rally led by junior forward Adrian Santos sparked the comeback.

But Teng scored on a layup then completed an and-one in the next play as La Salle uncorked a 10-0 blitz that had UE reeling with a 61-50 advantage.

The Warriors would not recover from that as the Archers went on to a 2-0 start for the first time since 2007, when they last won the championship.

"It's (2-0 record) a nice start," said coach Gee Abanilla, who himself is a rookie in the UAAP wars. "But we're still trying to figure out what works and what doesn't. It's a good thing we survived this game."

Teng paced the Taft-based crew with 16 points and five rebounds even as Jovet Mendoza and LA Revilla contributed with 11 markers apiece.

UE, on the other hand, were led by Roi Sumang's 20 points, five rebounds and three assists while Santos wounded up with 14 markers and 14 boards, 10 of them on the offensive end.

The scores:

UST (71) - Mariano 21, Teng 16, Abdul 14, Fortuna 11, Ferrer 4, Bautista 3, Lo 2, Pe 0, Daquioag 0, Afuang 0
ADMU (70) - Ravena 19, Salva 17, Slaughter 9, Tiongson 8, Buenafe 5, Sumalinog 4, Elorde 3, Chua 3, Golla 2, Gonzaga 0, Erram 0
Quarters: 12-27, 28-43, 58-54, 71-70


DLSU (67) - Teng 16, Mendoza 11, Revilla 11, Torres 7, Van Opstal 5, Vosotros 5, Dela Paz 4, Torres 3, Andrada 2, Tampus 2, Manguera 1, Paredes 0, Gotladera 0, Webb 0

UE (59) - Sumang 20, Santos 14, Javier 6, Olayon 5, Galanza 5, Villarias 3, Sumido 2, Razon 2, Mena 2, Belleze 0, Valdez 0, Hernandez 0, Flores 0, Duncil 0

Quarters: 13-11, 29-22, 43-39, 67-59