This Video of Serena Williams's Daughter Cheering Her on at the U.S. Open Is Pure Joy

It's official: Alexis Olympia is her mom Serena Williams's biggest fan.

On Saturday, the three-year-old adorably cheered on the tennis star during her match against Sloane Stephens at the 2020 U.S. Open — and her dad, Alexis Ohanian, shared the sweet mother-daughter moment on Instagram.

In the precious clip, little Olympia is seen excitedly pointing down to the court and mouthing the words "mama" to Ohanian. Looking up into the stands, Williams spots her family, and returns their love with an enthusiastic wave. Though no other fans were allowed to attend the competition due to the coronavirus pandemic, Olympia's cheerleading skills arguably made up for that fact.

After her victory, Williams answered a reporter's question about what she hoped Olympia saw while watching her play. "Well, I forgot she was coming out, so I hope that she saw her mama fighting," the 23-time Grand Slam champion said. "Hi, Baby. I don’t think she was paying attention, between you and me. She may have been playing with some princesses upstairs."

In between playing dress-up and princesses during quarantine, Serena's mini-me has also been helping her mom prep for this year's event. Earlier this summer, Williams shared a series of photos of her and Olympia stretching on the tennis court in matching purple unitards, and just last week, the toddler was candidly photographed intently watching the 38-year-old practice for this weekend's match while sitting courtside.

RELATED: Serena Williams Turned Daughter Olympia's Shirt Into Her Own Crop Top

Next, Williams will compete against Greece's Maria Sakkari, and if successful, she'll win her 24th Grand Slam title. But no matter the outcome — Olympia will be there, rooting for her mom in the stands.