Dominika Cibulkova has insisted that nothing less than her best performance would have been enough to beat two-time champion Victoria Azarenka.

The 11th seed defeated the Belarus hitter in three sets to advance through to the last eight, and after the match she admitted that she was delighted with her showing in the Rod Laver Arena.

The 25-year-old said: "I had to believe in myself because the first set that I played today was really, really good. My forehand was working and I was doing all that I could.

"But she started to step into the court and serve much better so I had to find something extra. I had to play really well today, and I felt like I did that."

Cibulkova will now play world number one Serena Williams in the quarter-finals.