Serena rolled back the years at Australian Open

'I'm good at rallying and I have to embrace the things I'm good at'

Serena Williams said she was moving around the court as well as she has in a long while after beating Simona Halep in the quarter-finals of the Australian Open on Tuesday.

World number two Halep is no slouch around the court, and the pair shared 52 rallies of five shots or more during a heavyweight contest on Rod Laver Arena.

Williams won 30 of them and joked that it had been a 'long minute' since she felt she would more often than not walk away from such exchanges with the point.

"I think 1926, the summer of 1926 I think was the last time I felt that," the 39-year-old smiled.

"But I'm good at rallying and I have to embrace the things I'm good at. I'm good at playing power, I'm good at hitting a hundred balls."

"And that's one thing that's unique about me that I just need to kind of accept and embrace and just be good at both."

In the second set of Tuesday's match, Williams displayed great mobility to win successive points after long rallies -- one of 21 shots, one of 13 -- and secure what proved to be a decisive break of serve.

"Movement has always been one of my strengths, and so it's actually more natural for me to move than for me not to," she added.

"So it was just kind of, 'Oh, that's how I used to move', so it's pretty good. I'm happy that I'm doing that again and that I put it back into my game."

Williams, who has never failed to reach the final after getting to the last four at Melbourne Park, will play Naomi Osaka in the semi-finals.

The seven-time Australian Open champion was reluctant to talk about what kind of challenge the Japanese third seed would present on Thursday.

"First of all, I'm in the semi-final. That's pretty awesome. So that's exciting," she said.

"And then it doesn't matter who I'm playing really in the semi-final. It's a semi-final of a Grand Slam. No one gets there by chance, so I have got to be ready."