Melbourne: Agnieszka Radwanska blamed a tough Australian Open schedule after bombing out against Dominika Cibulkova on Thursday, saying back-to-back matches had left her feeling like a "half-mummy".

The Polish fifth seed appeared to have the pedigree against Cibulkova, ranked 24th in the world, but their semi-final was a mismatch as the Slovak raced through 6-1, 6-2.

Afterwards Radwanska said she felt like she was playing in "slow motion" after coming through a tense three-setter against defending champion Victoria Azarenka just a day earlier.

"I felt like I was in slow motion today. I had a couple of tough matches, especially yesterday," she said.

"When I played a very tough match, very high level yesterday, playing the next day is always tough," Radwanska added.

The Pole was drawn in the bottom half of the women`s draw, meaning she had to play her quarter-final just a day before the semis. The women`s final is on Saturday.

"I knew I was the playing in the second half so of course I wouldn`t have a day off. In that case, that day off would be really a lot for me," she said.

Radwanska also fell to lower-ranked opposition in her previous Grand Slam semi-final appearance, against Sabine Lisicki at Wimbledon last year.

"It was similar, I think," she said, when asked to compare the two matches. "(Today) I think I had a bigger chance even when I was, like, half-mummy."

Radwanska also needed three sets against Yulia Putintseva and Anastasia Pavlyuchenkova earlier in the tournament, and she admitted the cumulative effort had left her feeling wiped out.

"We`re just human beings, we`re not machines," she said. "Sometimes it happens -- sometimes you`re just exhausted."