Svetlana Kuznetsova has said that she feels fresh after a long injury lay-off towards the end of last year.
The former US Open and French Open champion beat Caroline Wozniacki today to reach the Australian Open quarter-finals.
Kuznetsova missed several months of the season and after dropping down the rankings, said that she is feeling the benefits of good off-season preparation.
"I am really happy with the result," she said after the match. "I was a bit disappointed with the second set but I kept fighting.
"I had some knee problems last year but I had a good pre-season. I am feeling fresh and it's showing on the court.
"I never stopped loving the game. I was tired [after so many matches] but now I am feeling fresh again."
Kuznetsova will play either Victoria Azarenka of Elena Vesnina in the next round.