Ana Ivanovic on Tuesday said the thrill of beating Serena Williams left her "emotionally drained" in her Australian Open quarterfinal loss to Eugenie Bouchard - but she still believes she is playing the best tennis of her life.

The Serb, who won the Auckland International en route to Melbourne Park, could not keep her win streak going against the emerging Canadian teen, who won 5-7, 7-5, 6-2 to set up a last-four clash with Li Na.

But the former world No 1 said she was encouraged by her early season resurgence and was eyeing a return to the top 10 after struggling to hit the big time since winning the 2008 French Open.

"If at the beginning of the (southern hemisphere) summer someone told me this would be the outcome of it, I would agree to it," said the 26-year-old, who was also hampered by nagging injuries to both legs.

"I had some really good wins, some very emotional wins, and a lot of positive things came out of it.

"Obviously, it is very disappointing the way it ended. On a positive note, I feel like I played maybe the best tennis of my life.

"I just want to keep my head up and keep working hard, improve on the mistakes I made."

Ivanovic, who has admitted she struggled to deal with the fame and expectations that came with winning Roland Garros and becoming world No 1, said beating Williams in the fourth round was a highlight. But it left her drained ahead of the Bouchard clash.

Ivanovic also came through a tough three-setter against Australian favorite Samantha Stosur in the previous round.

"It's very hard because when I came into tournament, I saw my draw. It was quite tough. I had to battle through my matches," she said.

"Also I had a few very emotional wins, so today I really felt I was a little bit flat. But, you know, it's just another learning experience.

"Even though I didn't play my best, today I felt I still had chances. I didn't quite use them well, wasn't aggressive enough, had way too many errors.

"But it is something to learn from and move on."

Ivanovic, whose bubbly personality and family links to Melbourne have made her popular in Australia, said she aimed to return to the top 10. She was ranked 14 ahead of the Australian Open.

"It would be amazing to get back into the top 10. That would be something I really want to push hard towards," she said.

"It's about working hard and being consistent, showing the game I've been showing over and over again.

"And I felt very, very proud and happy about the way I was playing, in Auckland and also here. I see a very bright year."