Such is the depth of feeling between Serena Williams and the crowds at the Australian Open that the world No.


1 is now happily taking mid-match tactical advice from her fans.

Down a set on Monday and struggling against free-swinging Spaniard Garbine Muguruza, a spectator at Rod Laver Arena yelled out, advising Williams to readjust and use more spin.

The American took the comment on board and turned the fourth-round encounter around, winning 2-6 6-3 6-2 to advance to a quarter-final against last year’s Open runner-up, Dominika Cibulkova from Slovakia.

“My fan coach was yelling out `use some spin Serena’ and I was like `okay, okay’,” said Williams, who remains on track for a sixth Australian Open title and a first since 2010.

“It’s been really great to hear my name throughout the whole stadium.

“I don’t get that everywhere so it feels good.

“When you win often, sometimes people want other people to win and they forget that you want to keep winning too.

“But I get that (level of support) every year in Australia and that’s why this is my favourite place to come.

“I really love it so much.”

Williams and the 24th-seeded Muguruza had split their previous two encounters – both of which were one-sided, in sharp contrast to Monday’s two-hour marathon.

The American had also dropped the first set of her third-round clash against Ukraine’s Elina Svitolina.

For the second straight year, the diminutive Cibulkova is also making a run deep into the Open, the No.11 seed from Slovakia charging into the last eight with a 6-2 3-6 6-3 victory over two-time Open champion Victoria Azarenka.

After battling injuries and personal issues in 2014, the Belarusian entered the first grand slam of the year without a seeding, although she shaped as the most dangerous floater in the draw.

But it was Cibulkova who triumphed on Monday, winning in two hours and 10 minutes.

Cibulkova’s best-ever performance at a grand slam came last year at Melbourne Park when she advanced all the way to the final before losing to China’s Li Na.

“Today was an extremely good match from my side, a high level of tennis,” said Cibulkova.

“The first set, the way I played, was just really, really (good) – no mistakes.

“I was going for my shots and I was just doing the right things.

“… then in the third set I just knew I had to go for it more than 100 per cent – to be much more aggressive.”

Excitement machine Madison Keys advanced to her first major quarter-final with a comprehensive 6-2 6-4 victory over namesake and fellow American Madison Brengle.

Keys completed dominated the winners’ count 38-3, progressing to a last-eight clash against compatriot Venus Williams.

The seven-time grand slam winner won through with an upset 6-3 2-6 6-1 triumph over sixth seed Agnieszka Radwanska.