The Lady Troopers looked primed in finishing off the Lady Eagles, who missed the services of spiker Fille Cainglet, in just three sets after a dominating first set.
But Ateneo fought back and was able to clinch a set with better reception and crisp attacking led by Alyssa Valdez.
Army head coach Sgt. Rico de Guzman remained complacent amid Ateneo taking the third set and even pulling to within reach in the fourth.
“I let my second stringers play to let my players enjoy the game before we go up against Sandugo and Cagayan,” said De Guzman in Filipino. “I knew we will win even if the match went into the fifth set.”
Michelle Carolino unleashed majority of his 20 points in the deciding set, where Army seized control early, 13-6.
Ateneo moved to within three before Jacqueline Alarca put the game to bed with a kill as the Lady Troopers improve to 4-1, good for second place behind the undefeated Sandugo-San Sebastian squad.