Ready to Pop! Serena Williams Shows Off Her Round Baby Bump in Fitted Grey Dress

The living legend showcased her bump progress in a tight grey dress in mid-July. "I waddle now but only at night after a long day…" she shared on Twitter that same day.

Serena Williams has been documenting her pregnancy on social media since April, and she’s only looking more radiant as her due date grows near.

The tennis champion, 35, showed off her growing baby bump in a new Instagram post on Sunday. She wore a sleeveless grey dress as she posed for a couple of mirror selfies in a bathroom.

Williams left the images without a caption, but fans had plenty to say.

“Beautiful as always !! You have that glow !!” one commenter said, as others guessed whether she’s carrying a girl or a boy.

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RELATED VIDEO: Serena Williams and Alexis Ohanian Expecting First Child

The mom-to-be and her fiancé, Reddit co-founder Alexis Ohanian, are expecting their first child together this fall.

Williams and Ohanian opened up about the pregnancy, and their sweet love story, in a headline-making cover story for Vanity Fairs August issue.

In the article, Williams revealed that she took six pregnancy tests and handed them all to Ohanian in a paper bag to break the news to him.

“If you would have told me last year in October or November that I would have a baby, not be pregnant but have a baby, I would have thought you were the biggest liar in the world,” she said.

“This is kind of how I am right now. This is happening sooner than later, and it’s going by so fast.”

Williams is making the most of her pregnancy, including spending time in the French Riviera on a babymoon last month.

For the mini photo shoot, Williams wore a long black dress and blue silk kimono-style robe decorated with a multicolored flower print.

Ohanian, 34, gushed about becoming a parent during a recent appearance on CNBC’s Squawk Box, telling the hosts that he’s sure Williams will be a wonderful mother.

“She’s very good at a lot of things,” he said. “And well on her way to being an awesome mom too.”