US Open 2017: Karolina Pliskova, Svitolina and Ostapenko reach third round

Karolina Pliskova has to reach the US Open final to have a chance of retaining her world number one ranking

World number one Karolina Pliskova beat Nicole Gibbs in three sets to reach the US Open third round.

The Czech 25-year-old saved seven of nine break points to win 2-6 6-3 6-4 against the American in New York.

Pliskova had been on the back foot for much of the match but broke to love in the seventh game of the final set.

Shelby Rogers and Daria Gavrilova made history by playing the longest women's singles match in US Open history at three hours and 33 minutes.

American Rogers dropped to her knees in tears on Court 19 after beating the Australian 7-6 (8-6) 4-6 7-6 (7-5).

Shelby Rogers won 132 points and Daria Gavrilova 133 in their marathon three-setter

She will next play Ukrainian fourth seed Elina Svitolina who beat Russia's Evgeniya Rodina 6-4 6-4 in one hour and 22 minutes on Arthur Ashe Stadium.

Next up for Pliskova is China's 27th seed Shuai Zhang.

The 2004 champion, Svetlana Kuznetsova, saw her outside chances of taking the world number one ranking slip away as she lost to Japan's Kurumi Nara 6-3 3-6 6-3.

The Russian, who struggled with a wrist problem, is the fifth of the top eight seeds to lose before the third round.

Latvia's French Open champion, 12th seed Jelena Ostapenko, reached round three with a 6-4 6-4 win over Romanian Sorana Cirstea.

Home favourites Madison Keys, who is seeded 15th, and 20th seed Coco Vandeweghe both progressed in straight sets.

Keys saw off German Tatjana Maria 6-3 6-4, while her compatriot beat Tunisian Ons Jabeur 7-6 (8-6) 6-2.

Meanwhile, American world number 91 Jennifer Brady thrashed Czech Republic's 23rd seed Barbora Strycova 6-1 6-1 in just 56 minutes in New York.

Polish 10th seed Agnieszka Radwanska progressed with a 7-5 6-2 win over Yulia Putintseva of Kazakhstan.

Qualifier Kaia Kanepi, a five-time Grand Slam quarter-finalist but ranked 418 after injury problems, beat Yanina Wickmayer 6-4 6-2.

• Live scores, results and order of play

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