Former world number one Serena Williams will make a surprise comeback at the Mubadala exhibition event in Abu Dhabi next Saturday, as she gears up for her Australian Open title defence in January.
The decision to play in the United Arab Emirates should virtually confirm Williams' participation at Melbourne Park.
The 36-year-old has not played since clinching a 23rd Grand Slam singles title 11 months ago, after revealing she was pregnant during the tournament and taking time off to give birth to her first child, Alexis Olympia in September.
Williams will return with a match against Latvia's French Open champion Jelena Ostapenko, making them the first women to compete in the previously male-only event.
"I am delighted to be returning to the court in Abu Dhabi for the first time since the birth of my daughter," she said in a statement released by the tournament organisers on Sunday.
"The Mubadala World Tennis Championship has long marked the beginning of the men's global tennis season and I am excited and honoured to be making my comeback as part of the first women to participate in the event."
The former world number one can equal Margaret Court's all-time record of 24 Grand Slam titles, although she will have to make do with a low seeding Down Under after slipping to 22nd in the rankings.
Williams' comeback raises the prospect of a renewal of her one-sided rivalry with Maria Sharapova, after the Russian's own comeback earlier this year from a doping ban.
It also provides a boost the Australian Open, after two-time champion Victoria Azarenka pulled out of the warm-up event in Auckland over the ongoing custody battle that has stopped the Belarusian from playing since Wimbledon in July.
Serena claimed an Open-era record 23rd major title by beating older sister Venus 6-4, 6-4 in this year's Australian Open final, a feat made all the more remarkable by the fact that she was two months pregnant.
Ostapenko broke through with a stunning French Open title, and the 20-year-old will take on Serena for the first time.
The Mubadala event had already seen men's world number one Rafael Nadal and three-time Grand Slam winner Stan Wawrinka withdraw.
The six-strong men's field in Abu Dhabi does feature Serb Novak Djokovic, who will also be making his comeback.
The 12-time Grand Slam champion has not played competitively since his quarter-final loss to Tomas Berdych at Wimbledon because of an elbow injury.