Britain’s Emma Raducanu will face 23-time Grand Slam singles champion Serena Williams for the first time in her career on Sunday.
The pair have been drawn together in the first round of the Western and Southern Open in Cincinnati.
Earlier this week, Williams suggested she would soon retire from tennis, saying she will be “evolving away” from the sport after the US Open.
Raducanu is preparing to defend her US Open title later this month.
The British number one won the Flushing Meadows tournament last year as an unseeded 18-year-old, 22 years after Williams won her first Grand Slam singles title in New York, aged just 17.
The winner will face either Victoria Azarenka or Kaia Kanepi in the second round of the Cincinnati tournament.
In the men’s event, Rafael Nadal, who has a bye to the second round, will play for the first time since suffering an abdominal tear at Wimbledon that forced him to withdraw before his scheduled semi-final against Nick Kyrgios.
British number one Cameron Norrie faces Denmark’s Holger Rune and Dan Evans will take on Serbia’s Filip Krajinovic in the first round, while Andy Murray meets Taro Daniel of Japan in qualifying.