Queensland teenager Oliver Anderson has won through to his first ATP World Tour main draw after upsetting American Tim Smyczek in qualifying at the Brisbane International.
The 17-year-old, give a wildcard into the qualifying tournament, downed the world No.109 6-7 7-6 6-2
Anderson had beaten another American, world No.150 Dennis Novikov, in three sets on Saturday, the result certain to lift his own ranking of 813.
The youngster's win wasn't the only surprise on day one, with Swiss fifth seed Timea Bacsinszky the first seed to bow out after losing 6-2 6-1 to Russia's Anastasia Pavlyuchenkova.
Other first-round winners in the main draw included Dominika Cibulkova, Andrea Petkovic and Alize Cornet.
Cibulkova, beaten by Li Na in the final of the 2014 Australian Open, is on the comeback trail after Achilles-related surgery.
She recovered from being 4-3 and 0-40 down on her serve in the third set to hold off Belgium's Yanina Wickmeyer, 3-6 6-4 6-4.
A host of big names will be in action today, including Grigor Dimitrov, Victoria Azarenka and Aussie pair Sam Stosur and Sam Groth.
Dimitrov will feature in arguably the match of the day against French No.5 seed Gilles Simon.
Newcombe Medal winner Sam Groth will take on Korea's Hyeon Chung, while Stosur has drawn qualifier Jana Cepelova.
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