Michael Smith and Jemele Hill agree that Serena Williams has nothing left to prove in tennis but can see her returning to the game someday. (0:55)

It's another love game for Serena Williams: She is pregnant, and based on the timeline she offered, she already was when she won the Australian Open.

A spokeswoman for Williams, Kelly Bush Novak, wrote in an email to ESPN and other media outlets Wednesday: "I'm happy to confirm Serena is expecting a baby this fall."

The 23-time major champion will not play again in 2017 due to her pregnancy and plans to return in 2018.

Williams posted a photo of herself standing sideways with the caption "20 weeks" on Snapchat earlier Wednesday then deleted it.

serenawilliams/Snapchat

Williams, 35, did not comment beyond the photo and two-word caption.

She announced in late December that she was engaged to Reddit co-founder Alexis Ohanian.

Williams hasn't played since winning the Australian Open in January -- a little less than 12 weeks ago. She pulled out of her next two scheduled events at Indian Wells and Miami, citing a left knee injury. Her only other tournament this year was in Auckland, New Zealand, where she lost in the round of 16.

Tennis' next major tournament is the French Open, which starts May 28. Wimbledon begins in early July, and the US Open is in late August. If Williams is 20 weeks pregnant, she would be due in early September.

"We're excited for Serena," WTA CEO Steve Simon said in a statement. "This is wonderful news and we wish her the very best. We'll look forward to seeing her when she's back competing again."

There is recent precedent for tennis players to return to action after becoming mothers. Kim Clijsters retired briefly to start a family then came back to tennis and won three Grand Slam titles. Victoria Azarenka, a former No. 1 and major champion, has announced she will be getting back on tour after having a baby last year.

Williams' 23 Grand Slam singles titles are a record for the Open era, which began in 1968. She broke a tie with Steffi Graf after winning the Australian Open. Only one woman has won more: Margaret Smith Court, who claimed some of her 24 titles during the amateur era.

Information from The Associated Press was used in this report.