Makarova held on for a gritty 5 - 7 6 - 3 6 - 2 win over China 's Zhang Shuai .
Hours later she withdrew , complaining of a gastro - intestinal illness .
Makarova held on for a gritty 5 - 7 6 - 3 6 - 2 win over China 's Zhang Shuai , but hours later she withdrew , complaining of a gastro - intestinal illness .