Muguruza triumphs in Brisbane
Garbine Muguruza was forced to dig deep before eventually seeing off Samantha Stosur in the first round of the Brisbane International.
The Spanish player prevailed 7-5 6-7 7-5 in a fluctuating encounter that lasted just under three hours.
Muguruza, who will play Daria Kasatkina in the second round, is 10/1 to win the Australian Open, which starts later this month.
Meanwhile, the number five seed Svetlana Kuznetsova eased to a straightforward 6-2 6-4 triumph over Louisa Chirico and the number eight seed Roberta Vinci won an epic encounter with Kateryna Bondarenko 7-6 6-7 7-6.
In the first round of the Shenzen Open, Simona Halep beat the former world number one Jelena Jankovic 6-1 3-6 6-3.
Elsewhere, the British number one Johanna Konta thrashed Turkey's Cagla Buyukakcay 6-2 6-0 in a first-round match that lasted less than an hour.
Konta, who will play American Vania King in the second round, said afterwards: "I'm really enjoying my time in Shenzhen."
Konta is 14/1 to win the Australian Open, while Halep can be backed at 1212/1 to triumph in Melbourne and Serena Williams at 5/2.
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