The Swiss star, who won her third straight Australian Open last weekend and is ranked second in the world, gave herself a pep talk after losing the first set.

``I want to get back to the No. 1 spot and I won the Australian Open,'' she said. ``Then I lose here in my first round? No way! Come on! You've got to fight!''

Sugiyama, ranked No. 25, got off to a fast start with some big serves and accurate shots down the lines. In the final two sets, Hingis frustrated Sugiyama with long rallies and angled returns.

``Ai was very tough,'' Hingis said. ``She was giving 100 percent, maybe 200, at the beginning. ... I was surprised the way she played. She was very fast and didn't miss anything.''

Top-ranked Lindsay Davenport, the defending champion, begins play Thursday with a second-round match against Mary Joe Fernandez, a 6-1, 6-2 winner over Croatia's Iva Majoli.

Monica Seles also advanced to the quarterfinals, beating Sarah Pitkowski 6-1, 6-3. Seles dropped a semifinal match to Hingis in the Australian Open, her first loss ever in the tournament.

``Obviously, I had a great tournament in Australia,'' Seles said. ``But at the same time, Martina beat me very easily (6-2, 6-4). So there is a long way to go to really play consistently against someone like Martina, Lindsay and some other players.''

In a first-round match, Steffi Graf routed Samantha Reeves 6-0, 6-1. Graf last played in the tournament in 1997, when she withdrew from the final against Hingis because of a knee injury.

``My knee is doing very well,'' the seven-time Wimbledon champion said.

In other first-round matches, Mariaan de Swart beat Miho Saeki 6-3, 6-4, and Elena Likhovtseva beat Elena Tatarkova 4-6, 6-4, 6-2.