Serena Williams returns to US Open - as a fan

Serena Williams set Flushing Meadows abuzz on Saturday as the 23-time major winner appeared at the US Open - as a fan - for the first time since stepping away from tennis two years ago.

The six-time winner dominated New York throughout her career and fittingly made an emotional goodbye in Flushing Meadows, when she played her final match against Australian Ajla Tomljanovic in the third round of the 2022 tournament.

The tension of competition was gone on Saturday as Williams stepped on to the blue carpet decked out in a denim ensemble, all smiles and at ease as she flashed peace signs and smiled for the cameras.

"I feel like to me she's always been that upbeat and happy person. Obviously we're all in the zone when we're about to compete, and so that's different when you don't play anymore," said Caroline Wozniacki, Williams' longtime friend.

"But at the end of the day, I think she's always been, you know, a happy and outgoing person."

Williams was seen chatting with world number one Iga Swiatek at the players' gym ahead of the Pole's third-round match against Anastasia Pavlyuchenkova, which she won in straight sets.

"Even though we met before and for, like, couple of years we have been on the same sides and on tour together, she's still, like, star-striking me," Swiatek told reporters.

"It was nice that she approach me, because I wouldn't, for sure, find courage to do that if it was the other way."

The American watched Italian number one Jannik Sinner beat Australian Chris O'Connell and American Jessica Pegula get past Spain's Jessica Bouzas Maneiro at Arthur Ashe Stadium, where she played her final match.

Wozniacki, who included Williams as a bridesmaid in her wedding, won her third-round meeting with French qualifier Jessica Ponchet at the Grandstand and joked that she was "pretty mad" that Williams was not in attendance for her match as well.

"Serena is obviously still very busy. I think when you've been such incredible at something, I think you'll always have the opportunity, you'll always be great at whatever you put your mind to," said Wozniacki.

"I love hanging with her. I love talking to her. You know, I love the support that I get from her, as well."