Why Osaka has an 'upper hand' over Kvitova in Aus Open final

US Open champion Naomi Osaka may be best known for her fierce power game but her coach Sascha Bajin believes the Japanese 21-year-old's fitness and mindset should give her an edge in the women's final against Petra Kvitova.

Osaka will bid for her second Grand Slam title in succession against twice Wimbledon champion Kvitova on Saturday, having claimed her maiden major in New York last year by upsetting Serena Williams in the final.

Bajin said he wanted Osaka to take the game to lefthander Kvitova in the same way she did against another Czech in Karolina Pliskova in the semi-final, when she hammered 56 winners and clubbed 15 aces.

"I kind of want her to approach the match like she approached Pliskova. (Kvitova) is also a big server. Just kind of like the opposite, because she's a lefty. Same mindset," the German coach told reporters at MelbournePark on Friday.

"You know, both of them are very dangerous off the first two, three shots, but I believe once the rally keeps going, Naomi with her current state of mind and physique has the upper hand."

Osaka's mental strength has shown in the way she has avoided the trap of first time Grand Slam winners crashing at their next major and knuckled down to overcome three-set tests to book her first final at Melbourne Park.

Bajin was impressed at how his fourth-seeded charge had re-started training for the new season after a short break.

"Yeah, she really wants it. You know, people say they want it, but she really wants it," he said.

"You know, we had an unbelievable great season last year, but after having just two weeks' break, she came back and showed up and really worked her butt off.

"Yeah, she's a hard worker, and she wants to be, and that's why she's here."

Adding additional weight to Saturday's clash, Kvitova and Osaka are also playing for the world number one ranking.

Osaka was crushed to miss out on winning her third career title at the Brisbane International warmup, upset by Lesia Tsurenko in the semi-finals, but had taken lessons from the disappointment to Melbourne, Bajin said.

"I always think you learn more from your losses than from your wins. Naomi is definitely one of those persons, as well," he said.

"Obviously she takes losses very hard, because it means a lot to her and she works really hard to keep winning and wants to win every match.

"But there's not so much I have to say afterwards. It's just more like emotional management, just to be there for her and tell her that it's all right and losses happen to everybody.

"But thankfully she learns from it a lot, and it shows here."