Can Zheng spring a surprise on defending champ Sabalenka?

Aryna Sabalenka has blown all-comers off court on her march to the final of the Australian Open and China's Zheng Qinwen will need to produce something extraordinary to deprive her of back-to-back titles on Rod Laver Arena on Saturday.

The Belarusian is the first woman since Serena Williams in the middle of the last decade to reach consecutive finals and, while she has a long way to go to match feats of the American great, they do have something in common.

When combined with mental strength and consistency, raw power is a quality that almost guarantees success in the women's game.

Sabalenka has always had the power and, since addressing the frequent on-court meltdowns that once blighted her career, has shown a frightening level of consistency at Grand Slams.

The 25-year-old has now reached the semi-finals or better at the last six majors, going on to win her first Grand Slam title in Melbourne and losing the U.S. Open final to American teenager Coco Gauff last year.

Sabalenka got a measure of revenge for that Flushing Meadows defeat in a high quality semi-final on Thursday but, crucially, gave the impression that she would not have been absolutely devastated had she lost the tight contest.

"Worst case, I'm like 'Okay, I'm gonna lose this tournament, and it's less points to defend next year. Then that's it'," she said of her approach to the tournament.

"That's kind of like helping me to just stay focused and just try my best in each match."

Her more relaxed approach is reflected in a new pre-match ritual, signing the bald head of her performance coach Jason Stacy.

While Sabalenka would match compatriot Victoria Azarenka's feat of 2012 and 2013 by retaining her title, Zheng is hoping to give China its second Australian Open crown a decade after Li Na won the first.

Zheng, voted the most improved player on the WTA tour last year, was the only seed in the top half of the draw to survive into the quarter-finals and knows she will have her work cut out in her first Grand Slam final.

"She's the biggest hitter on the tour. She got the biggest serve, biggest forehand, big backhand. She's a really complete player," the 12th seed said after her semi-final win.

"I haven't faced any top seeds in the earlier rounds but, you know, it's a match, so let's see what happens."

Sabalenka beat Zheng 6-1 6-4 in their only previous meeting in the quarter-finals of last year's U.S. Open but said she was wary of the 21-year-old's forehand.

"She's playing really great tennis," she said. "She's a really nice girl and really playing really great tennis once again. It's going to be a great battle."

Zheng, who moved to Li's hometown of Wuhan as a child to pursue her tennis dream, was prepared to accept there was an element of destiny in her winning a place in the final 10 years to the day after her hero won the title on Rod Laver Arena.

"My dream is not just the final," she added. "I'm almost there, but I know this little distance is still far away. I'm not there yet. There is still something that needs to happen."