Stosur defeated Erika Sema 6-4, 6-2, with a pair of breaks in each set. Stosur won just nine more points over the course of the match against Sema, a Tokyo-born player ranked No. 164 in the world, but finished off four of her six break chances while fighting off five of the six Sema managed.
Chang Kai-Chen beat McHale 6-3, 7-6 (7-5) in a match that took nearly 2 hours. Both players were on the defensive much of the day as McHale had 11 break chances, converting four, and Chang had 12, finishing off five.
Japan's Misaki Doi got by Julia Cohen 7-5, 3-6, 6-0 in a 2-hour, 40-minute battle by losing just seven points in the third set.
But other Japanese players joining Sema on the sidelines after opening-day action were Ayumi Morita, who fell 6-3, 6-2 to Jamie Hampton, and Kimiko Date-Krumm, who lost to Casey Dellacqua 6-3, 3-6, 6-4.
Also, Heather Watson beat Polona Hercog 6-4, 6-4 and Pauline Parmentier breezed past Mathilde Johansson 6-2, 6-2.
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