It was a thrilling, action-packed start to the Season 81 men's basketball title series, as the defending champion Ateneo Blue Eagles downed the University of the Philippines Fighting Maroons at Mall of Asia Arena on Saturday.

Relive the action in this massive slideshow, courtesy of ABS-CBN News photographers George Calvelo and Mark Demayo.

Ateneo big man Angelo Kouame drives to the hoop. George Calvelo, ABS-CBN News

Blue Eagles wing man Thirdy Ravena drives to the basket. Mark Demayo, ABS-CBN News

Fighting Maroons forward Jun Kent Manzo's path is blocked by a Raffy Verano. George Calvelo, ABS-CBN News

Ateneo's Gian Mamuyac passes the ball in a tight situation. Mark Demayo, ABS-CBN News

Blue Eagles wing man Thirdy Ravena goes up for a block. George Calvelo, ABS-CBN News

Fighting Maroons veteran Paul Desiderio hustles for the loose ball. George Calvelo, ABS-CBN News

Ateneo's Gian Mamuyac drives against UP's Bright Akhuetie. Mark Demayo, ABS-CBN News

Ateneo's Antonio Asistio fires from outside. Mark Demayo, ABS-CBN News

Ateneo's Thirdy Ravena flubs a dunk. Mark Demayo, ABS-CBN News

Ateneo's Angelo Kouame drives to the hoop. Mark Demayo, ABS-CBN News

UP fans rally their team under the slogan, "Atin 'To." Mark Demayo, ABS-CBN News

UP fans cheer their team on as the game progresses. Mark Demayo, ABS-CBN News

The crowd is split between the blues of Ateneo and the maroons of UP. Mark Demayo, ABS-CBN News

The Ateneo side of the gallery. Mark Demayo, ABS-CBN News

Emotional Ateneo fans cheer their team on. George Calvelo, ABS-CBN News

Ateneo coach coach Tab Baldwin talks to his player Antonio Asistio. George Calvelo, ABS-CBN News

Ateneo coach Bo Perasol signals a play to his team. Mark Demayo, ABS-CBN News

Fighting Maroons center Bright Akhuetie after hyperextending his left knee during a play underneath the basket. Mark Demayo, ABS-CBN News

Fighting Maroons center Bright Akhuetie grimaces in pain after suffering an injury. Mark Demayo, ABS-CBN News

UP players Paul Desiderio, Jun Manzo, and Javier Gomez de Liano react to teammate Bright Akhuetie’s injury. George Calvelo, ABS-CBN News

A fan of UP reacts in the dying minutes of the game. George Calvelo, ABS-CBN News

Jerson Prado of UP and Angelo Kouame of Ateneo contest the rebound. George Calvelo, ABS-CBN News

Paul Desiderio of UP and Thirdy Ravena of Ateneo. George Calvelo, ABS-CBN News

Players chase the loose ball after a play. George Calvelo, ABS-CBN News

Ateneo’s Thirdy Ravena drives to the basket. George Calvelo, ABS-CBN News

Angelo Kouame of Ateneo blocks the shot of UP’s Paul Desiderio. George Calvelo, ABS-CBN News

Maroons' Juan Gomez De Liano reacts to a call. Mark Demayo, ABS-CBN News

The Ateneo Blue Eagles after winning Game 1 of the UAAP Season 81 men's basketball finals. Mark Demayo, ABS-CBN News

Senator Richard Gordon joins the Ateneo community in singing their hymn after the win. George Calvelo, ABS-CBN News

Ateneo fans sing their hymn after the win. George Calvelo, ABS-CBN News

• UAAP finals: Blue Eagles survive spirited UP fight to win Game 1

• UAAP: Pacquiao roots for UP, promises to take team to US bout if they win

• UAAP finals: UP’s Bright Akhuetie returns to game after exiting on a stretcher

• UAAP finals: Celebrities, fans react after Ateneo beats UP in Game 1

• ANALYSIS: On biggest stage, Ateneo’s top guns outshone Fighting Maroons’ stars

• Why Tab Baldwin doesn’t want to play Fighting Maroons in UAAP finals

• UAAP finals: Coach Bo on Akhuetie knee — ‘Wala naman daw serious injury’

• UAAP finals: Game 1 has given Perasol confidence that UP can beat Ateneo

For more sports coverage, visit the ABS-CBN Sports website.