SYDNEY, Australia - Australian No.1 Ashleigh Barty wrapped up the third home win of the day at the Sydney International late on Tuesday, making her way into the quarterfinals with a 7-6(4), 6-1 win over compatriot Ellen Perez.

The first set found the No.341-ranked wildcard, a University of Georgia graduate who turned pro last year, putting up a plucky fight, coming from a break down to force a tiebreak against the World No.19.

Perez had shown flashes of potential with qualifying wins in 2017 in both Sydney (over Kateryna Kozlova) and the Australian Open (over Tadeja Majeric), and she was able to force play with her forehand on multiple occasions against an unusually passive Barty.

However, once Barty had found the range with her slice and passing shots, she stepped up a level to take the tiebreak and run away with the second set.

"For me, the polish isn't quite there," said the 21-year-old afterwards. "But I think the beauty is I get the chance to play another match tomorrow to try and fix things that we're after. We're not far off. I think it might just click in the middle of a match and I go: 'Oh, you know what? I feel great.'"

Barty's victory completed a positive day for Australian players that had begun with Samantha Stosur snapping an eight-match losing streak on home soil to defeat lucky loser Carina Witthoeft 4-6, 7-5, 6-3, a replacement for injured No.7 seed Julia Goerges, in a first-round match.

The 33-year-old had reached her second ever final here in 2005, losing to Alicia Molik - but her Sydney record since then was a modest 5-9 before today.

"Don't even know when the last time [I won here] was," joked Stosur about her history. "Whenever that was, it's nice to do it again and repeat it this time around."

The World No.42 will face another Australian in the second round - Daria Gavrilova, who battled past another wildcard compatriot in Olivia Rogowska 6-4, 1-6, 7-5. In a match that had to be delayed when a storm hit as Gavrilova was poised to serve for it at 5-4 in the final set, the World No.25 committed nine double faults and was broken three times.

On the prospects of playing a fellow Australian in front of a home crowd, the veteran Stosur was equanimous.

"Yeah, that's happened numerous times throughout my career," she shrugged. "I have actually practiced with Liv twice this week already. Dasha warmed me up this morning. We all know each other very well... there are not really going to be any secrets out there."

For Barty, the number of Australians in action illustrated a new depth in the home ranks.

"It was just Sam and sort of Casey [Dellacqua] for so many years," she reflected. "Now it's nice to see these young girls, girls a couple years younger than me who I've known for a long time, coming through and getting an opportunity."

These breakthroughs mean additional challenges for her, though, as the top-ranked Australian.

"It's very tough playing other Aussies, especially in Australia - I think rankings go out the window when you play countrywomen," Barty said.

Gavrilova was in agreement about finding it tough to play a compatriot - unsurprisingly, given her scoreline - and the depth in Australian tennis, also shouting out 18-year-old Jaimee Fourlis, who scored her first WTA win in the Hobart International this week.

The 23-year-old said she relished the opportunity to play at home, though.

"I love it!" she exclaimed. "Like, of course there is added pressure, but I just... think of the crowd and I get a lot of young girls and boys supporting me."

Ultimately for Stosur ahead of her second-round clash with Gavrilova, the key to playing teammates, friends and compatriots is sportsmanship. 

"We'll give it our best and shake hands at the end and that will be it," said the 2011 US Open champion sagely.

In rare non-Australian news from Sydney, 2013 runner-up Dominika Cibulkova notched up a second straight-sets victory this year with a 6-4, 6-4 second-round defeat of Elena Vesnina. The Slovak was joined in the quarterfinals by Barbora Strycova, who ousted Ekaterina Makarova 6-4, 6-1 and will now face Barty for a place in the final four.