Williams appeared to take lightly her first-round opponent, 18-year-old Spanish qualifier Maria Jose Martinez. After dropping the second set to the 152nd-ranked Martinez, the reigning Wimbledon and U.S. Open champion picked up her game in the third and prevailed, 6-3, 2-6, 6-0.

The top-seeded Kuerten, who finished 2000 as the year-end No. 1, overcame a thigh injury early on to outduel fellow South American Gaston Gaudio of Argentina, 7-5, 6-7 (6-8), 6-3, 7-5, in a match that lasted nearly 3 1/2 hours.

Hingis, the top seed on the women's side, began her quest for a fourth Australian Open title in five years by crushing Katalin Marosi-Aracama of Hungary, 6-1, 6-1, in 39 minutes.

Williams, seeded third, overcame 45 unforced errors and seven double faults to extend her winning streak on hard courts to 26 matches.

"It's a good thing to have a little test, especially since I haven't played any tournaments prior to this," said Williams, who missed last year's Australian Open with wrist tendinitis. "I didn't feel like I was playing my top form throughout the match. I think I served very well, so I was happy with that."

After failing to go an entire year without a Grand Slam singles title for the first time since 1996, Hingis is trying to start 2001 with her first major since winning here in 1999. She was denied a fourth straight title in Melbourne with a loss to Lindsay Davenport in last year's final.

"I came into this tournament with two victories, so I felt pretty confident," said Hingis, who took the title in Sydney on Saturday. "I didn't want to make any mistakes that were not necessary, and I served very well from the beginning on."

Serena Williams had an easier time than her older sister in her opening-round encounter with Janet Lee of Taipei. Seeded sixth, Serena Williams downed Lee, 6-1, 6-4, in just over an hour. The Williams sisters are in the top half of the draw and could meet in the semifinals.

"I think my game is going to get better as the rounds go on and I think now it's not my game, it's just a mental thing," Serena Williams said. "I have to take it one match at a time and not look too far much ahead."

Kuerten, the reigning French Open champion, received treatment on his left thigh late in the first set, but managed to play through his discomfort to gut out the win. The Brazilian fired 18 aces, but had to overcome a whopping 78 unforced errors and nine double faults.

"I just felt a little bit tight at the start of the match. It wasn't anything that got me worried," said Kuerten, who has not advanced past the second round in four previous Australian Opens. "It's always tough for me to play well here. so I knew it would be a difficult match, my first match this year. He (Gaudio) played some good points and I had ups and downs for most of the match."

Next up for Kuerten is former top-10 player Greg Rusedski of Britain.

In other men's seeded action, fourth seed and 2000 semifinalist Magnus Norman of Sweden recovered from a slow start to defeat Stephane Huet of France, 1-6, 7-5, 6-1, 7-6 (7-5).

Fifth seed Yevgeny Kafelnikov of Russia started his bid for a third straight finals appearance in Melbourne by cruising into the second round. Kafelnikov, the 1999 champion and 2000 runner-up, needed only 82 minutes to dispatch Jens Knippschild of Germany, 6-1, 6-4, 6-2.

Kafelnikov broke Knippschild six times, produced 29 winners and was helped by his opponent's 56 unforced errors in improving to 23-4 lifetime at the Australian Open, including 14-1 since 1999.

Being overtaken as Russia's top player by U.S. Open champion Marat Safin last year does not affect Kafelnikov, whose success in Australia also includes the Olympic gold he captured at the Sydney Games in October.

"It doesn't bother me at all," Kafelnikov said. "(Safin) had a great year last year, winning seven tournaments, including the U.S. Open, so he deserves to be in front of me."

Kafelnikov may not have such an easy time in the second round as he will face Nicolas Kiefer of Germany, a quarterfinalist here last year. Kiefer, who has beaten Kafelnikov in their last two meetings, dispatched Wayne Black of Zimbabwe, 6-3, 7-5, 6-2, on Tuesday.

Seventh seed Lleyton Hewitt of Australia escaped from his tough first-round encounter with former top-10 player Jonas Bjorkman of Sweden with a 7-5, 4-6, 2-6, 6-3, 6-2 victory.

Also, 10th seed Wayne Ferreira of South Africa got past Karim Alami of Morocco, 6-3, 7-5, 6-4, and No. 11 Franco Squillari of Argentina topped David Sanchez of Spain, 6-3, 6-4, 6-2.

Seeded Frenchmen Arnaud Clement and Sebastien Grosjean also were first-round winners. Clement, seeded 15th, defeated Tommy Robredo of Spain, 6-3, 6-2, 7-5, and Grosjean, seeded 16th, downed Ivan Ljubicic of Croatia, 6-0, 7-6 (8-6), 6-4.

In another matchup of note involving former world No. 1s, Spain's Carlos Moya dumped 1998 runner-up Marcelo Rios of Chile, 6-3, 6-3, 6-2.

Among other seeded women in action, No. 7 Mary Pierce of France, the 1995 winner and reigning French Open champion, disposed of Austria's Sylvia Plischke, 6-1, 6-3.

Also, No. 9 Elena Dementieva of Russia, a semifinalist at last year's U.S. Open and the Olympic silver medalist, beat American Lilia Osterloh, 6-4, 6-3; two-time semifinalist Amanda Coetzer of South Africa, seeded 10th, defeated Sonya Jeyaseelan of Canada, 6-2, 6-4; 1999 finalist Amelie Mauresmo of France, seeded 13th, dumped Ai Sugiyama of Japan, 6-3, 6-3; and No. 16 Amy Frazier of the United States dispatched French qualifier Laurence Andretto, 7-5, 6-4.