World number one Ashleigh Barty has been drawn in the same group as Naomi Osaka at the WTA Finals in Shenzhen.
French Open champion Barty and Australian Open winner Osaka will be joined by Petra Kvitova and Belinda Bencic in the Red Group.
The Purple Group includes US Open champion Bianca Andreescu, Wimbledon winner Simona Halep, Karolina Pliskova and Elina Svitolina.
The tournament in China takes place from 27 October to 3 November.
Barty, who won her first Grand Slam title at the French Open, heads the field on her maiden appearance, having becoming the first Australian since 1976 to be ranked world number one.
The 23-year-old is one of three debutants, alongside Canadian teenager Andreescu, who has won 37 of her 42 matches in an incredible breakout year, and Swiss 22-year-old Bencic.
Defending champion Svitolina, 25, and two-time Wimbledon champion Kvitova, 29, are the only players in the field to have previously won the title.
The tournament, which also includes a doubles event featuring the year's top eight teams, has a record total prize fund of £10.8m.
Chinese city Shenzhen is hosting the season-ending event for the first time after it moved from Singapore in a 10-year deal.
No Williams or Konta - who missed out?
British number one Johanna Konta fell short of a first appearance in the season-ending finals, despite a fine year that saw her reach the French Open semi-finals, along with runs to the Wimbledon and the US Open quarter-finals.
Konta, 28, finished 11th in the Race to Shenzhen to earn a place in this week's WTA Elite Trophy in Zuhai - the second-tier finals tournament - but pulled out of the event after having some pain in her knee.
American great Serena Williams is also missing after being overtaken in the standings by Bencic following the Swiss player's victory at the Kremlin Cup in Russia.
The 23-time Grand Slam champion has not played since losing to Andreescu in September's US Open final.
Other high-profile absentees include Germany's three-time Grand Slam champion Angelique Kerber, Denmark's 2017 Tour Finals winner Caroline Wozniacki and Spain's former Wimbledon champion Garbine Muguruza.
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How does the tournament work?
The finals are the culmination of the WTA season and the singles title is contested by the eight players who have accumulated the most ranking points from 52 tournaments - including the four Grand Slams - over the year.
The eight singles players are seeded in terms of points accrued and split into two groups of four in a draw, which took place on Friday.
The groups are played in a round-robin format over the course of the week, with the top two players in each qualifying for the semi-finals on Saturday.
The winners meet in the final on Sunday, 3 November, at 12:30 GMT (19:30 local time).
|Ashleigh Barty (Australia)||1||French Open champion, becoming world number one|
|Naomi Osaka (Japan)||3||Winning Australian Open for back-to-back Slams|
|Petra Kvitova (Czech Republic)||6||Australian Open runner-up, first Slam final since career-threatening injury|
|Belinda Bencic (Switzerland)||7||Reaching US Open semi-finals, winning Dubai title|
|Karolina Pliskova (Czech Republic)||2||Winning a tour-high four titles, reaching Australian Open semi-finals|
|Bianca Andreescu (Canada)||4||Winning US Open after stunning breakthrough year|
|Simona Halep (Romania)||5||Realising childhood dream by winning Wimbledon|
|Elina Svitolina (Ukraine)||8||Reaching semi-finals at Wimbledon and US Open|