A bogey mishap on the par-5 18th ruined what could’ve been an explosive start for the 25-year-old Rosales, who has so far churned out four top 10 finishes in 15 tournaments but remained hopeful to finally bag the elusive crown in the coming weeks.
Hitting it straight and through the par-72 Evian Masters Golf Club course, Rosales birdied two of the first three holes then chipped in for another on the par-5 No. 7 to go 3-under at the turn.
But the five-time RP Ladies Open champion somewhat slowed down at the back, hounded again by poor putting as she missed a couple of makeable birdie putts before dropping a stroke on her way out.
Still, it was an otherwise solid start for the ace Filipina shotmaker, who hit all but one fairway in the day, missed just two greens and putted 30 times to lead the big bunch of two-under par scorers occupying seventh to 15th places.
Inkster and Ochoa both fired 66s under a hot and steamy day with Inkster overcoming a double-bogey 7 on the par-5 15th after hitting out of bounds with an eagle at the closing hole.
Ochoa, with a string of top 10 finishes and running eighth on the LPGA money list, opened with a stirring 29 at the front highlighted by four straight birdies from No. 4, including an eagle from 20 feet at the par-5 No. 7. However, she stumbled with back-to-back bogeys from No. 12 but birdied No. 16 and went out with a 37.
World No. 1 Annika Sorenstam struggled to match par on three birdies negated by a double-bogey seven at the 15th where she hit her tee shot out of bounds.
One of the most successful ever US College golfers during her time at the University of Arizona, Ochoa, for the third time, shot 29 for nine holes, her first first as a professional.
"This is my first trip to France and all my family are here, so it was a good time to do it," said the youngster.
"This year, everything is new to me, but this is one of the most beautiful places that I have ever been. I had a really good feeling today and it was very special."
American Rosie Jones was just one off the lead, while South Korea’s Jeong Jang and Britain’s Janice Moodie shared fourth spot on 68. The tiny Jang, who is just over five feet, finished tied sixth in the US Women’s Open three weeks ago, and continued her fine form with a five birdie round.
Britain’s Laura Davies had a chance of mixing it with the leaders until she hit into a flower bed and ran up a double-bogey seven at the 18th. She was furious to be denied a free drop, and then took two shots to get out of the red bizzie lizzies.
"It’s a flower bed and should be ground under repair," she claimed. "It’s not normal stuff on a golf course and I should definitely have been given a drop."