Paula Creamer carded a superb 64 to lead the way after the opening round of the Evian Championship.
Former U.S. Women's Open champion Creamer was not put off by the heat in France, as she kept her cool with seven birdies in a bogey-free round.
Creamer claimed the Evian Masters title aged 18 in 2005, though she has not led in a major since the 2010 U.S. Women's Open at Oakmont, and a wrist injury sustained in this competition in 2017 has seen her form drop, meaning she is now ranked 156 in the world.
Her lead is a slim one, however, with seven-time major winner Inbee Park - who is yet to triumph at Evian - among four players to have carded 65.
Ko Jin-young is one of those tied for second, and she looked in sharp form after winning the ANA Inspiration in April - a victory which saw her move to number one in the world rankings for 12 weeks.
Ko made eight birdies but bogeys on the second and 13th cost her the lead.