Australian Ajla Tomljanovic beat American Shelby Rogers in three sets, to join Sam Stosur, Casey Dellacqua and Jarmila Gajdosova under the Southern Cross in the women's second round.

Ajla who? Good question, as many casual tennis followers will know little about the David Taylor-coached Croatian who moved to Florida at the age of 12 before being granted Australian residency last year.

Joining Tomljanovic in the citizenship queue is Russian-born Daria Gavrilova, the long-time sweetheart of another former world No.1 junior, Luke Saville, and a first-round Open loser after winning the wildcard playoff last month.

All of which is helping to boost numbers in the elite ranks of the Australian women's game, which incoming director of performance Pat Rafter is pledging will benefit from more time and focus under his watch.

For while men's depth has improved to the point that there are 12 inside the top 200, the corresponding women's number – excluding Tomljanovic, who is only a local for grand slam purposes until her passport arrives – is five.

Why? Another good question, says Rafter.

"Maybe we just dropped the ball a little bit with the women. I'm still getting my head around what's happened. Same formula can be for the men and women ... make it more inclusive, and hopefully they enjoy themselves and get them through those teenage years and come out the other side."

Rafter makes it clear he does not favour waving cheque books at foreign players, and insists that is not what has occurred.

"There are obviously the girls who have seen Australia as a great avenue for their pathway; they've come over and wanted to become Australian, and we've got to make sure the public knows that Australia never goes actively out to players saying, 'Will you be part of our country?' They've come to us.

"And then you say to them, 'Yes, well, if you want to be part of Australia, then you can use our system,' so we've had a couple who have really good potential who are Australian now, and another group of young girls coming through in the next five years that could offer some really good depth, as well."

World No.29 Dellacqua is at pains to point out there are two Australian women inside the top 30, Stosur being the other, "which I know the men don't have. So I think sometimes the women get a little bit of a hard time."

Not that it bothers Dellacqua, who has just finished a career-best year and at Flushing Meadows in August was seeded at a major for the first time. Melbourne Park makes two.

"We know what we do – that's all that matters to me," said Dellacqua, 29. "I see Sam work tirelessly to perform at her best every day. That's all she does. I have so much respect for her in that regard. We both had great years. It doesn't annoy me. We're proud of what we achieve."

The next great hope, of course, was Ashleigh Barty, Dellacqua's friend, protege and former doubles partner, with whom she reached three slam finals in 2013.

Late last year the 18-year-old Queenslander, who won the Wimbledon girls' title at 15, announced she was taking an indefinite break from the game.

Dellacqua is confident Barty will be back, and she is adamant there is still time – late-blooming having often been the Australian way, and there being fewer teen prodigies anywhere these days.

She remains in regular touch with Barty, who is doing some junior coaching with her long-time mentor Jim Joyce and recently played a few low-key matches locally.

"She's doing great," said Dellacqua. "Yeah, she's up in Brisbane, spending lots of time with her family. I know she's got a new puppy. Important things in life.

"I miss her a lot on tour. She was my go-to person on tour. She kept me young. So I really hope to see her back soon. But, yeah, at the moment she's happy. You know, in time I think she'll be back and ready to go."

Meanwhile, on Thursday, as Hewitt seeks a 10th appearance in the third round against Benjamin Becker, he will officially have three Australian women for company: Stosur against CoCo Vandeweghe, Dellacqua versus Madison Keys and Tomljanovic, who plays American Varvara Lepchenko, before a possible meeting with sixth seed Agnieszka Radwanska in the third round.