Ash Barty caps breakout year with $20 million WTA Finals berth

World No.1 Ash Barty has become the first player to qualify for the season-ending WTA Finals in Shenzhen.

The 23-year-old, who won her maiden grand slam title at the French Open this year, will be making her singles debut in the October 27 - November 3 Finals.

The event offers US$14 million in prize money (AU$20 million).

‘NOT GOOD’: The major problem with Rafa Nadal's US Open triumph

"It's been a goal from the very start of the year to qualify for the WTA Finals," Barty, Australia's first women's No.1 since Evonne Goolagong Cawley in 1976, told the WTA website.

"I'm proud of the work my team and I have put in to get to this point, and I'm honoured to be among the top eight players of the season."

Barty will be the first Australian to compete at the season-ending tournament since Samantha Stosur in 2012.

The top eight singles players will face off in a round-robin format, with the winner taking home the Billie Jean King Trophy.

Andreescu surges up rankings

Barty reclaimed the No.1 spot on Monday less than a month after losing it, while US Open champion Bianca Andreescu moved up to a career-high fifth after her maiden grand slam win in New York.

Andreescu beat Serena Williams 6-3 7-5 in Saturday's final to maintain a 13-match unbeaten run, where she also won the Canadian Open, to break into the top 10 for the first time in her career.

"I don't want to take anything for granted. These are the moments you live for and I'm just beyond blessed," Andreescu, who moved up 10 places, said.

After taking the first set and leading 5-1 in the second, Andreescu was broken twice by 23-times grand slam winner Williams before eventually breaking back and winning the contest to become the first Canadian to win a major in the professional era.

"It definitely wasn't easy in the final against Serena Williams," the 19-year-old added.

"I think I'm most proud of how I'm able to get into my zone and I was able to block out the crowd too because they were really, really loud.

"If I didn't do that, I'm sure Serena would have won that second set so I'm really glad with how I handled everything."

Barty exited the tournament in the last 16 but regained the top spot after last year's champion Naomi Osaka was also knocked out at the same stage.

The Japanese, who also beat Williams in last year's final, slipped to fourth in the rankings with Czech Republic's Karolina Pliskova and Ukraine's Elina Svitolina leapfrogging her to move up to second and third respectively.

Wimbledon champion Simona Halep fell two places down to sixth while Williams fell one spot to ninth despite her run to the final.

with AAP