The New Zealand golfer Lydia Ko will need to win this weekend's season finale in Florida if she's to be named the LPGA Tour's player of the year.
Ko is one of nine players that could also win the season-long competition that is known as the Race to the CME Globe title.
Thailand's Ariya Jutanugarn currently tops the standings from Ko and Canadian Brooke Henderson.
Ko is tied for 16th after the opening round after firing a two under par 70 and is four shots behind the leader Shanshan Feng of China.
Jutanugarn opened with an even par 72 and is tied for 32nd.
Ko has won the title the last two years and came from third in the standings in 2014 with victory in the season-ending tournament.
Ko's position at the top of the world rankings is not under threat this week.
This week's winner will pick up a cheque for 700 thousand dollars, while there is a million dollar bonus for the winner of the Race to the CME Globe.
Ko has so far won 3.5 million dollars on the tour this year, including four wins.