US Open: Coco Gauff battles back to defeat Laura Siegemund in three sets

American hope Gauff, the sixth seed, was left frazzled by qualifier Laura Siegemund's incredible anticipation and volleying in the first set.

But the match swung after an epic 26-minute first game of the second set, a minute longer than Iga Swiatek had taken to win her first set against Rebecca Peterson.

In front of the watching former world heavyweight champion Mike Tyson, Gauff went toe-to-toe with the German at the net and finally converted a break point at the eighth attempt.

The pair slugged it out with some stunning rallies, firing volley after volley at each other in a match more akin to doubles than singles.

A niggly encounter boiled over when Gauff, tiring of the type of delaying tactics from Siegemund which would have had Premier League referees' chief Howard Webb in a lather, raged at chair umpire Marijana Veljovic.

The youngster could barely contain her delight when Veljovic deducted Siegemund a point for not being ready to receive, giving Gauff a 5-1 lead in the decider.

"Slow!" was Gauff's verdict on the match after closing out a 3-6 6-2 6-4 victory in two hours and 51 minutes.

"I mean it was a tough match," she added. "I wasn't playing my best tennis and Laura fights to the end. I managed to overcome some adversity so I'm happy to get through."

Gauff will play another teenager, 16-year-old Mirra Andreeva, in round two.

World number one Swiatek had earlier helped herself to a New York bagel to get her title defence off to the perfect start.

The 22-year-old from Poland dropped just eight points as she took the first set to love against Rebecca Peterson.

Sweden's Peterson did get on the board early in the second but Swiatek, bidding for a fifth grand-slam title, completed a comprehensive 6-0 6-1 victory in just 58 minutes.

"I really wanted to play solid and start the tournament with everything I practised on," she said.

"I'm happy to play such a great game and despite all the pressure and expectation I can still have fun on the court."

There was an upset on day one at Flushing Meadows with eighth seed Maria Sakkari from Greece bowing out 6-4 6-4 to Spanish world number 71 Rebeka Masarova.

Fourth seed Elena Rybakina, last year's Wimbledon champion, had no such trouble, dispatching Marta Kostyuk 6-2 6-1.

Victoria Azarenka, a three-time finalist, beat Fiona Ferro 6-1 6-2 and Czech 10th seed Karolina Muchova sank Storm Hunter of Australia 6-4 6-0.

READ MORE: US Open: Holger Rune crashes out after taking swipe at tournament organisers