The only Mexican woman in the draw put paid to sixth seed Madison Keys at the US Open on Tuesday, with 82nd-ranked debutante Renata Zarazua producing a 6-7 (10), 7-6 (3), 7-5 fightback win.

The winner earned her first defeat of a top 10 player after six previous failed attempts, advancing to the second round after more than three hours of battle over the reigning Australian Open winner.

Keys went out with 37 unforced errors and never was able to get her game uncranked.

Zarazua rallied from 3-1 down in the second set  to win it and level the match and broke the seed twice in the final set to grab the upset win.

“I was just trying to focus on the court. I just tried to find my way because I knew that when I retire, I’m going to be really happy about this and told myself to enjoy it,” the winner said.

She is the first Mexican to beat a top 10 player at a Grand Slam since Angelica Gavaldon defeated Jana Novotna at the 1995 Australian Open.

The world’s top junior, 16-year-old Julieta Pareja fell to ninth seed Elena Rybakina, with the Kazakh winner earning a 6-3, 6-0 win in just over an hour.

Pareja, last month’s Wimbledon junior runner-up in both singles and doubles, was competing in only her second match at the Tour level and facing her first-ever top 10 opponent.

“She’s really young and I think she plays really well for her age, especially with her nice technique, she has a great future ahead,” Rybakina said.

“The first match is always not easy, but I’m happy with the win. I think now I’m playing well and of course not at the level I want to be still, but slowly building step by step, taking it one match at a time, so we’ll see how it goes.”

Rybakina has never been past the third round at Flushing Meadows but reached hardcourt semi-finals at per three previous summer events.

Toronto WTA winner Victoria Mboko came through an on-court drama as opponent Barbora Krejcikova temporarily lost her racquet string dampener with the Canadian joining in the search for the precision bit of kit.

But after finding her opponent’s plastic widget on court, Mboko ended up taking a 6-3, 6-2 first-round loss to the former Wimbledon and Roland Garros champion.

Krejcikova advanced with 17 winners, claiming nine of 11 points at the net. The loss to Mbobko, who skipped Cincnnati after her home title this month, has been struggling with a wrist problem.

The Czech winner was reluctant to detract from the accomplishment of the Canadian teen. “It’s huge what she has achieved already. How well she played.

“When I was watching it (in Montreal) I was really happy she made it because it’s a huge huge victory for her. Good luck to her.”

Krejcikova, her ranking down to 62 after injury, earned only her ninth win of the season as she competed in her eighth tournament since her turn to action last May.

Two-time Wimbledon champion Petra Kvitova, who left the Tour to have a child and returned last with limited success after more than a year away, left the court in tears as she played her final match.

The 35-year-old Czech lost to Dnane Perry of France, winning just one game in the 52-minute match…

“I’m not sure what I’m gonna do. I should be a mom as well, so that’s what I’m gonna try. I really miss the time with my son,” Kvitova said.

“It’s just enough of tennis for me right now, but I do love the sport, so we’ll see what the future will bring. Tennis gave me the most which I can have.

“It gave me the happy memories for everything, even (when) I didn’t win.” 

Unseeded 34-year-old veteran Anastasia Pavlyuchenkova, a quarter-finalist 11 years ago, started her campaign over Dayana Yastremska, 6-7 (5), 7-6 (5), 6-4

Main photo:-Renata Zarazue putting out Madison Keys in first round match – by Mark Greenwood/Grandslam Tennis