US Open: Coco Gauff and Caroline Wozniacki advance at Flushing Meadows

Gauff, who burst onto the scene when she beat Venus Williams on her way to the fourth round at Wimbledon aged 15, ousted the Russian rookie 6-3 6-2.

The sixth seed, still only 19, had to come from behind to beat Laura Siegemund in a drama-filled three-setter on Monday, but she had a far more gentle work-out this time on Arthur Ashe.

Gauff is fast becoming a live contender for the title this year having won 13 of her 14 matches since losing in the Wimbledon first round to fellow American Sofia Kenin.

She lost a first-set tie-break against Andreeva at this year's French Open but came back to win in three.

Gauff said: "I just learned then to be aggressive, because if you give her something she is going to take advantage.

"She has a great future in front of her - I think she is going to be back on this stage many more times."

There was another home success in New York when Taylor Townsend beat Brazilian 19th seed Beatriz Haddad Maia 7-6(1) 7-5.

World number one and defending champion Iga Swiatek beat Daria Saville 6-3 6-4 to set up a meeting with her good friend Kaja Juvan, with whom she went out for dinner just a few days ago.

"She's my best friend on tour. She's one of the most, like, honest and I think smart people on tour," said Swiatek.

"I'm happy that she's my friend, but yeah, we've got to play against each other. It's a tricky situation, but I think we both know how to be professional and just play the match and that's all."

In the night session on Arthur Ashe, former world number one Caroline Wozniacki, making her grand slam comeback on a wild card after more than three years away and having had two children, beat 11th seed Petra Kvitova 7-5 7-6(5).

"Being out here, this couldn't be better and if you'd asked me three years ago, to be on this court and beating the world number 11, it feels really special," said the 33-year-old Dane.

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