Sakkari, a semi-finalist in New York last year, took charge in the early stages and marched into a one-set lead before being let down by a series of unforced errors as Wang claimed her first career victory over a top-10 player.

Despite Sakkari's superior experience, Wang's heavy hitting from the baseline came to the fore in the second set as she took a 5-3 lead before clinching it after a double-fault from Sakkari.

Both players matched each other in the decider but it was Wang who raised her game in the key moments, breaking Sakkari at 6-5 to take the win and reach the third round of a Grand Slam for the first time.

Sakkari's defeat capped a difficult couple of days for Greek tennis following the shock first-round exit of men's fourth seed Stefanos Tsitsipas at the hands of Colombian qualifier Daniel Elahi Galan.

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