World number two Serena Williams has appeared to announce on social media that she is pregnant.

The 35-year-old posted a picture of herself on Snapchat posing in a mirror with the message: "20 weeks" before deleting the post.

If confirmed, the American, who won a record 23rd Grand Slam in Australia this January, will miss most of the remaining tennis season.

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This includes three Grand Slams - the French Open, Wimbledon and US Open.

Williams, who will return to world number one next week, would be eligible to retain her ranking under the WTA Special Ranking Rule if she is ready to play her first tournament within 12 months of giving birth.

US Open Tennis responded to Williams' message by saying: "@serenawilliams will have a new pride & joy to hug and call her own soon! Congratulations on the exciting baby announcement!"

The news - if confirmed - means Williams won her 23rd Grand Slam title at the Australian Open roughly eight weeks into her pregnancy.

The baby could be born during this year's US Open, and we are therefore very unlikely to see Serena compete in another Grand Slam before the French Open of 2018. That event will take place four months before her 37th birthday - but do not write off a woman who will return to world number one on Monday.

Victoria Azarenka is a useful guide. Even though she is eight years younger, Azarenka gave birth to her first child in December, returned to serious training in March and is targeting the WTA event in Stanford at the end of July for her return to the WTA Tour