Australia's tennis women are surging in the busy end-of-season calendar -- but it's still the evergreen Ajla Tomljanovic who will be returning as their standard bearer this week.

Kim Birrell became the latest Aussie to make a big breakthrough at the weekend when she reached her maiden WTA final in the Japan Open.

The success of the 26-year-old Queenslander followed another first-time final appearance by 22-year-old Olivia Gadecki the previous month when she reached the Guadalajara Open championship match.

But despite the success of her younger compatriots, it's 31-year-old Tomljanovic, battling back excellently after a season which began with injury and illness woes, who will return to No.1 in the Australian women's rankings this week.

By qualifying for last week's Ningbo Open in China during a successful stint in Far East tournaments, Tomljanovic, who's done more than anyone to keep the flag flying for Australian women's tennis since the retirement of the all-conquering Ash Barty, will rise to No.81 in the next world rankings.

Boosted by her recent victory in the smaller Hong Kong WTA 125 event, that will push her ahead of current Australian No.1 Gadecki, who'll fall two places behind at No 83.

Behind them will be Maya Joint (110), who reached her first WTA 125 final in Warsaw in July, with Birrell moving up 39 places in the rankings to No.111 after her big week in Osaka where she started out as a qualifier in the WTA 250 Japan Open and made it all the way to her first final.

On a busy Sunday at the hardcourt event in Osaka, Birrell, a former Aussie No.1 herself, had to play two matches in the space of a few hours after the previous day's play had been wiped out by rain.

It all started well as the 26-year-old Queenslander won her sixth straight match, including two qualifiers, in her first ever WTA semi to beat home favourite Aoi Ito 6-3 6-4 and power into her maiden tour championship match.

But when she returned to the court just over an hour later, it was another qualifier, Dutchwoman Suzan Lamens, the world No.125, who proved much the stronger, winning comfortably 6-0 6-4 in 73 minutes.