World number two Ariya Jutanugarn leads the first women’s Olympic golf event since 1900 after a six-under-par 65 in the opening round at Rio 2016.
Thailand’s Jutanugarn, 20, the British Open champion, is one shot ahead of South Korean pair Inbee Park – a seven-time major winner – and Sei-young Kim.
British number one Charley Hull is three shots off the lead, and team-mate Catriona Matthew is level par.
New Zealand’s Lydia Ko, the teenage world number one, carded a 69.
Golf returned to the Olympic programme for the first time since the early 20th century when Great Britain’s Justin Rose won the men’s event last week.
But, while Rory McIlroy, Jason Day and Jordan Spieth were among the high-profile male absentees, nine of the world’s top 10 female players are competing in Rio.
The absentee is South Korea’s 10th-ranked Ha Na Jang, who only missed out because her nation already had its full complement of four players.
Park, 28, was named in the quartet after recovering from a thumb injury, which stopped her defending the British Open title last month.
She had not played competitively for two months but five birdies in a bogey-free round helped her take an early clubhouse lead.
However, Jutanugarn – who won her first major at Wentworth in Park’s absence – continued her fine recent form to climb to the top of the leaderboard.