Born: April 24, 1997
Coach: Sean Foley
Previous Olympics: 2016
During a stellar amateur career, she became the youngest person to ever win a professional tour event at the 2012 NSW Open, aged 14, and then became the youngest-ever winner on the LPGA Tour at the Canadian Open, but couldn't claim the $300,000 winner's prize.
She defended her title the following year and after finishing runner-up at the Evian Championship - one of the five LPGA Majors - Ko finally turned pro, winning three tournament in her first year and spending 84 weeks at the world No.1 ranking.
She won her first Major at the 2015 Evian Championship and another at the ANZ Inspiration the following year, when she also took the Olympic silver medal, behind Korean rival Inbee Park, at Rio.
But Ko parted with coach David Leadbetter at the end of 2016 and has spent subsequent season struggling to regain her form. This year, she fell just short of victory at the ANA Inspiration and broke a three-year winless drought at the Lotte Championship two weeks later.
Ko is currently ranked No.10 in the world an coached by Sean Foley, who has previously worked with Tiger Woods and Rio men's champion Justin Rose.