South Korea's Kim Sei-young is set to defend her title at the season finale CME Group Tour Championship this weekend at Tiburón Golf Club in Florida in the United States, as some top newcomers are set to miss the event.
Kim held off England's Charley Hull by a single shot to be crowned the 2019 champion.
Her compatriot A Lim Kim won the US Open as a rookie last week, but opted not to join the field this week, with competition starting tomorrow and running until Monday.
Germany's Sophia Popov, who won the AIG Women's British Open in August, will also miss the event due to her not being a member of the Ladies' Professional Golfers Association (LPGA) Tour, not earning the points that would make her eligible for other competitions.
With the field being expanded to 72 players, Popov could only finish 82nd, but would have finished 16th if the British Open counted.
Another South Korean, world number one Ko Jin-young, will compete too and now sits 46th in the 2020 LPGA standings after just three starts on the Tour, missing a lot of the season due to the COVID-19 pandemic having opted to stay in her home country.
Last week at the US Open, Ko finished joint second behind A Lim Kim to fill her with confidence coming into the final tournament.
"This week is my best finish at the US Open, so I can play next week as well," said Ko at the event.
"I'm really thankful.
"This season is too tough with coronavirus, so I want to say thanks to the United States Golf Association and all the volunteers."
Other stars from last year include American pair Danielle Kang and Nelly Korda who were a further shot behind Hull and two behind Kim.
Kang sits second in the overall standings behind South Korea's Inbee Park, with the pair a fair distance ahead of Kim Sei-young in third.
The four-day competition will end the LPGA Tour for 2020.