Defending champion and seventh seed, Spain's Garbiñe Muguruza lost to Ukrainian Lesia Tsurenko at the Cincinnati Masters tennis tournament here.
Tsurenko, ranked 44th, overturned a first set deficit to send Muguruza, ranked 9th, packing 2-6, 6-4, 6-4 in two hours on Wednesday, reports Efe.
With this victory, the Ukrainian progressed to the round of 16 where she will face Russia's Ekaterina Makarova, who defeated France's Alize Cornet in straight sets 6-2, 6-0.
In other matches, world number two, Denmark's Caroline Wozniacki retired with a left knee injury during her second round match against the Netherlands' Kiki Bertens, after the latter won the first set 6-4.
Earlier, the American third-seed Sloane Stephens, finalist in Montreal last week, easily defeated Germany's Tatjana Maria 6-3, 6-2, and will face Belgium's Elise Mertens.
Mertens, seeded 14th, came back from a set down to beat Sweden's Rebecca Peterson 3-6, 6-2, 7-6 (1).
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Belarus' Aryna Sabalenka eliminated Czech ninth-seed Karolina Pliskova 2-6, 6-3, 7-5 and will now face France's Caroline Garcia, seeded sixth in the tournament.
Prize money worth $2.9 million is distributed in the women's section of the Cincinnati Masters, according to the WTA webpage.
--IANS
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