IRIGA overcame a late surge by Baguio and posted a 25-22, 25-17, 26-24 win on Wednesday in the Shakey's V-League Season 13 Open Conference at The Arena in San Juan.
The Lady Uragons looked set for a smooth straight-sets win when when Baguio raced to a 20-15 in the third.
Iriga scored five straight to tie it at 20-20 and wound up on top after a see-saw battle.
Maria Tsuchiya saved match point, 24-24, but Iriga scored the next two points to even its record to 1-1.
Grazielle Bombita led the way with 15 points, while Jose Rizal University standout Shola Alvarez chipped in 11 points as the Lady Uragons bounced back after a loss to Laoag on Monday.
"Nakaka adjust na, 'yung last na game parang naninibago pa sa venue, 'yung crowd 'yung ganito na 'yung nasa live coverage sila, nag-adjust naman ang team," said Iriga coach Elvis Pabilona.
Tsuchiya finished with 12 points.