Switzerland's Martina Hingis is through to the last eight of the $1.2 million Pan Pacific Open in Japan after a convincing 6-1, 6-2 victory over Germany's Marlene Weingartner.
In her first appearance since losing Saturday's Australian Open final to Jennifer Capriati, Hingis raced through the first set in just 19 minutes.
The Swiss world number four threw in some delicate lobs and showed exquisite touch at the net to open a 3-0 lead in the second set but suffered a brief lapse in concentration before wrapping up the match in 47 minutes.
"Mentally, the first couple of days were tough after Melbourne," she said. "I had so much time to think about it on the plane here, but the motivation is there to get back the number one ranking."
Hingis, the top seed in the tournament, has won the event on three previous occasions and twice finished as runner-up. She said she was confident of winning her 40th career singles title on the fast indoor courts this week.
"The expectations are for me to win and I put that kind of pressure on myself because I am used to being number one," she said.
Hingis will face Thailand's Tamarine Tanasugarn in Friday's quarterfinals.
swissinfo with agencies
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