Defending event champion Fitzgibbons had overcome countrywoman Gilmore to take the Rip Curl Pro title the previous weekend, but it was 24-year-old Gilmore who stood out in the Taranaki opener with the day's high score of 17.75 in her heat three victory over local surfers Sarah Mason and Gaby Sansom.
“Sarah has beaten me at this event in the past,” Gilmore said.
“And last night I was wondering how Gaby surfed, so I looked her up online and she surfs really well.
"Luckily there were lots of waves in that heat and I stayed busy and kept my mind off them. It’s pretty tiring having all these events so close together.
"This morning when I woke up I was praying they would have a lay-day, but the waves were really fun so I’m glad we ran.”
The 21-year-old Fitzgibbons edged American Lakey Peterson for first place in Heat Four with a 14.60, while Laura Enever posted four of the top five wave scores en route to an impressive 17.05 score which bested Hawaii's Malia Manuel and fellow Aussie Rebecca Woods.
“It was a dream to win back-to-back at Bells last week,” Fitzgibbons said.
“Then coming here to New Zealand it’s all about adapting to the beachbreaks. I love surfing here, it’s similar to home.
"I think all the community support at this event is unreal. It looks like the swell is going to hang around for the week which is exciting.”
Enever said: “I think I was trying to force things a bit too much at the start. I caught a couple of waves all the way to the shore and didn’t get much of a score.
"So I changed my game plan to try to do the biggest turns I could and it paid off. I did two turns and got an 8.60 (out of a possible 10), and after that I got some other big scores. It was great way to finish a heat.”
Elsewhere, tour rookie Sage Erickson caused an upset by besting 2011 ASP Women's World Champion Carissa Moore and local favourite Paige Hareb in an exciting and closely-contested Heat Five, while Courtney Conlogue made it two American heat winners by claiming Heat Six with a score of 15.15 and Aussie Tyler Wright's 15.00 was enough to see off Coco Ho of Hawaii and Brazillian Jacqueline Silva to round out the opening day's action.
The Dow AgroSciences Pro is part of the New Zealand Surf Festival, which runs from April 11-15.
Heat 1: Laura Enever (AUS) 17.05, Malia Manuel (USA) 14.50, Rebecca Woods (AUS) 10.75
Heat 2: Tyler Wright (AUS) 15.00, Coco Ho (USA) 13.65, Jacqueline Silva (BRA) 6.00
Heat 3: Stephanie Gilmore (AUS) 17.75, Sarah Mason (NZL) 9.34, Gaby Sansom (NZL) 4.00
Heat 4: Sally Fitzgibbons (AUS) 14.60, Lakey Peterson (USA) 12.95, Justine Dupont (FRA) 9.80
Heat 5: Sage Erickson (USA) 11.50, Carissa Moore (USA) 10.50, Paige Hareb (NZL) 8.63
Heat 6: Courtney Conlogue (USA) 15.15, Pauline Ado (FRA) 12.50, Sofia Mulanovich (PER) 8.70