Beyoncé congratulates Serena Williams on the birth of her baby girl

And the internet can't cope...

Serena Williams has welcomed her first child with Reddit co-founder Alexis Ohanian, with the news breaking over the weekend.

The couple announced that they were expecting back in April, revealing that Serena was 20 weeks pregnant, and now they have reportedly welcomed their daughter, giving birth on September 1st.

While the new mother has yet to comment, Serena's coach confirmed the news that the baby girl had arrived, with news producer Chris Shepherd confirming on Twitter that the baby is 6 pounds, 13 ounces and that both she and her mum are doing well.

Since the arrival of her bundle of joy, fans have been taking to the internet in their thousands to send congratulatory messages.

Among those congratulating the 35-year-old Tennis Pro was proud friend Beyoncé who took to her own Instagram feed to dedicate a post to Serena.

'Congratulations Serena', posted Beyoncé alongside a photo of the Grand Slam champion from her Vogue September Issue shoot.

The photo, shot by Mario Testino, shows Serena holding her baby bump in a white flowing Donatella Versace gown, and was met by excited comments from the Single Ladies singer's 106 million followers.

Others to send their congratulations included Serena's coach Patrick Mouratoglou, who posted, 'Congratulations Serena Williams for your baby girl. I am so happy for you and I feel your emotion.'

He continued: 'Recover well and enjoy without limitation... Btw ... I wish you a speedy recovery ... we have a lot of work ahead of us.'

Sister and fellow tennis pro Venus Williams has also voiced her excitement, exclaiming 'words cannot describe.'

Congratulations to Serena and Alexis!