Christina McHale opened her Apia International campaign on a strong note with a straight-sets victory over fellow American Jennifer Brady in the first round of qualifying.
The No.2 seed breezed to a 6-1 6-3 win, setting up a second-round match against Czech Kristina Kucova, who overcame Magda Linette in three sets.
McHale is now the highest-ranked player remaining in the qualifying draw after No.1 seed Yaroslava Shvedova was stunned in straight sets by Naomi Broady.
Broady, of Great Britain, ousted Shvedova 6-1 6-4 in just 64 minutes.
It was a mixed day for the highest seeds in Sydney; 2014 tournament champion Tsvetana Pironkova, the No.3 seed, overcame a slow start to beat Patricia Maria Tig in straight sets, while fourth seed Louisa Chirico was shown the door by Slovak Jana Cepelova.
McHale, meanwhile, arrived in Sydney having beaten Sara Errani en route to the second round in Brisbane.
And she’d gleaned plenty of information on Brady after training with her compatriot throughout the off-season, and having practised with her just yesterday.
“It’s tough having to play a friend, but I think I played really solid today, so I’m happy just to get more matches in,” said McHale.
“I was pretty happy with the way I played. I just tried to keep the balls deep, neutralise her and use my forehand when I could.”
McHale ended the 2016 season ranked 45th, her first top-50 finish since 2012.
During the year she won her second career WTA title in Tokyo and stretched Serena Williams to three thrilling sets in the second round at Wimbledon.
Despite being one of her best years on tour McHale believed it was an “up-and-down” campaign and she was hoping to ascend further in 2017.
“I tried to get a lot stronger in the off-season so I spent a lot of time working on my fitness in the gym. And then (I’m) just trying to improve my court positioning a little bit as well,” she said.
“I’m still trying to get into my rhythm; I feel like the more matches I can play, the better. Maybe playing quallies here will be helpful to hopefully get a few matches in.”
Local fans were given something to cheer about when wildcard Ellen Perez scored the biggest win over her career over Kateryna Kozlova.
Perez, who is ranked No.651 and plays college tennis in the United States, , had until today played just one tournament above ITF level. That was the 2016 US Open, for which she won a Tennis Australian wildcard play-off to compete in the main draw.
The Aussie used her powerful left-handed game to overwhelm the 101st-ranked Kozlova 6-4 6-4.
She will next face Broady.
In other results, Croat Donna Vekic subdued Barbora Stefkova 7-5 6-2 and will next play No.8 seed Vania King, who beat Australian wildcard Olivia Tjandramulia 6-2 6-1.
Also progressing were Maria Sakkari of Greece and China’s Duan Ying-ying.