Carlota Ciganda and Maria Torres earned a share of the lead in round one of the Evian Championship after each shooting scores of 65 on Thursday.
Spaniard Ciganda was flawless throughout her opening 18 holes at Evian Resort Golf Club on the opening day of the fifth and final major of the season.
The 28-year-old, starting her round at the 10th hole, made three birdies on her opening nine holes and as many on her way home to sign for a score of six under.
Torres was one over through six, but two birdies in three holes before the turn preceded a birdie, birdie, eagle stretch between the 13th and 15th holes, while a further gain at the last saw her match Ciganda's score.
Austin Ernst is just one shot back at five under with her scorecard showing five birdies, an eagle and two bogeys.
Two-time major winner Ryu So-yeon is one of three players tied for fourth and two shots adrift of the leaders.