Top seed Lleyton Hewitt was pushed to three sets by a Japanese player for the second day in a row at the $860,000 Japan Open on Thursday.
The Australian eventually won 6-7 6-2 6-4 against third-round opponent Takao Suzuki, a wildcard entrant.
On Wednesday Hewitt dropped the second set in his win over Suzuki's compatriot Goichi Motomura, another wildcard in the draw.
"I was just trying to stay motivated," Hewitt said. "I was able to break serve early in the second set and that was key to getting control of the match."
&to=http://english.pravda.ru/science/ 19/95/380/13530_Sharapova.html' target=_blank>Sharapova, who had a tough second-round win over Australian Samantha Stosur on Wednesday, will face a strong challenge in the semi-finals on Friday from in-form Thai Tamarine Tanasugarn, a 6-1 3-0 winner over Hungary's Aniko Kapros who retired with a thigh strain.
Sharapova, who played in China and South Korea before coming to Tokyo, admitted her long trip was catching up with her.
"I am a little tired," she said. "I had a tough match yesterday, but I just have to stay positive and hopefully get a good night's sleep," informs Reuters.