Top seed Maria Sharapova won a tough all-Russian quarter-final over 12th seed Anna Chakvetadze 7-6 (7/5), 7-5 to reach the Australian Open semi-finals on Wednesday.
The win means Sharapova will face either tournament favourite Kim Clijsters or three-time champion Martina Hingis in the semis.
The 19-year-old, who has just reclamed the world number one ranking, admitted it was an unconvincing performance against a dogged opponent who refused to be dominated in her first Grand Slam quarter-final.
"I thought I was a little bit up and down, a bit scratchy," Sharapova said.
"When you're up a set and you have a break against a good player you can't let her back in the match and that's what happened.
"I'm definitely glad I got through and next time's going to be even tougher."
Sharapova took two hours 14 minutes to beat Chakvetadze, committing 41 unforced errors and six double faults in a tightly-contested match that featured nine breaks of serve.
She squandered two match points as she struggled to land a killer blow against her 19-year-old compatriot, finally emerging victorious when Chakvetadze failed to defend herself for the fifth time.
After winning through to her third Australian Open semi-final in a row, Sharapova acknowledged she would have to improve to get past either Clijsters or Hingis and reach the final.
{{/usCountry}}After winning through to her third Australian Open semi-final in a row, Sharapova acknowledged she would have to improve to get past either Clijsters or Hingis and reach the final.
{{/usCountry}}"It was very difficult, particularly serving because I didn't feel that we had easy rallies. I felt I had to work on every single point on my serve so I was definitely happy I could break in the last game," she said.
"I'm looking forward to a really tough match in the next round but definitely have to step it up and I hope I can go all the way this year and win it."
Chakvetadze showed her high-profile compatriot she would be in for a tough fight from the outset, when she forced Sharapova to defend three break points in her first service game.
She never gave up, taking Sharapova to a tiebreak in the opening set before the experience of her fellow Russian made the difference in the second.