Ashleigh Barty claimed the Brookwater Golf Club women's title near Brisbane with a commanding 7 and 5 triumph in the matchplay final.
The withdrawal of third-ranked Naomi Osaka means French Open will be missing two of the world's top three, after reigning champion Ashleigh Barty said earlier this month that she wouldn't return to defend her title.
World number one and defending French Open champion, Ashleigh Barty said it was a "difficult" decision but the health of her family and team came first.
Australian Ashleigh Barty retains the top spot although neither she nor world number two Simona Halep are taking part in the US Open.
Simona Halep feels that travelling from Europe for the US Open will be tough as there are no direct flights.
Former US Open champion Stan Wawrinka is the latest in the list of players who have decided to skip the Grand Slam, joining the likes of Rafael Nadal and Ashleigh Barty.
Rafael Nadal is preparing to play at the French Open this year as he looks to win his thirteenth title.
Nick Kyrgios, ranked just 40 but a major drawcard, last month blasted the ATP as "selfish" for pressing ahead with plans for the US Open, which is scheduled to start on August 31.
Ashleigh Barty is the biggest name so far to withdraw from the tournament, with her decision coming as the United States marked a grim milestone when its COVID-19 deaths topped 150,000.
World No.1 women's player Ashleigh Barty said she won't be travelling to the US due to the significant risks posed by the coronavirus pandemic.
Novak Djokovic, champion at the US Open in 2011, 2015 and 2018, described planned limits on player entourages as "really impossible".
A decision about the US Open -- played in New York -- is yet to be made, but its main draw is scheduled to begin on August 31.
Petra Kvitova, ranked 11th in the world, is chasing a 28th tour title, having lost only nine finals.
Ashleigh Barty has won her last three meetings with Petra Kvitova, including the quarter-finals of the Australian Open last month.
Ashleigh Barty beat Laura Siegemund 6-3, 6-2 in the Qatar Open while Sofia Kenin lost to Dayana Yastremska.
Ashleigh Barty stayed on top of the Women's Tennis Association rankings despite losing in the semi-finals of the Australian Open.
Sofia Kenin stunned world number one and home hope Ashleigh Barty to reach her first Grand Slam final at the Australian Open.
Ashleigh Barty beat American 18th seed Alison Riske 6-3, 1-6, 6-4 and next plays two-time Wimbledon champion Petra Kvitova.