New York, Aug 26 : Renata Zarazua staged an upset at The US Open by beating Australian Open champion Madison Keys to reach the second round.

The Mexican had scored her first ever Top 10 triumph with a gruelling 6-7(10), 7-6(3), 7-5 scoreboard to down No. 6 seed Keys.

Zarazua fell in six previous attempts against Top 10 talents, but secured a career-best result in three hours and 10 mins to book a Round 2 rumble with France's Diane Parry.

Zarazua, who trailed by a set and 3-0, is the first Mexican woman to defeat a Top 10 seed at a Grand Slam since Angelica Gavaldon took down Jana Novotna at the 1995 Australian Open.

Last year was the first time in the 27-year-old Mexican's career that she played in all four Grand Slam singles main draws. The two titles on her resume are both WTA 125s, a year ago in Charleston and, in 2023, Montevideo. Her career-high ranking is No. 51.

The Mexican has never advanced past the second round. She'll have that chance when she meets Diane Parry, a 6-1, 6-0 winner over retiring Petra Kvitova.

In another action, Mirra Andreeva made an impressive return to competition on Monday night at the 2025 US Open, dismissing a wayward Alycia Parks under lights in Louis Armstrong Stadium.

Andreeva had played just one match since Wimbledon due to an ankle injury, while Parks had arrived in New York fresh off her run to last week's WTA Monterrey semifinals.

Andreeva, however, played steady, tactically-astute tennis, breezing into Round 2 with a 6-0, 6-1 victory.

Andreeva arrived in New York without a win since her Round of 16 triumph at Wimbledon over Emma Navarro seven weeks ago.

Earlier this year she won back-to-back WTA 1000 titles in Dubai and Indian Wells, and reached consecutive Grand Slam quarterfinals at Roland Garros and Wimbledon.

/IANS