SYDNEY, Australia (AP) _ Ian Thorpe has three Olympic gold medals and a silver, and he may not be done yet.

The 17-year-old Australian sensation could swim in the 400-meter medley relay later this week, giving his countrymen another chance to see their hero in the pool.

Spurred by rousing cheers of "Thorpey! Thorpey!," Thorpe gave the Aussies a 3½-second lead as they set the world record in winning the 800 freestyle relay Tuesday. He was ahead by two-body lengths at one point.

It was Australia's second relay victory over the American men, who narrowly lost to the host country in the 400 freestyle relay last weekend.

Tom Malchow, however, gave the U.S. team reason to celebrate by winning the 200 butterfly and lowering his own Olympic record for the third time in two days.

His medal was the Americans' sixth gold in four days.

Thorpe left no doubt why he's adored Down Under. He established a world record in winning the 400 freestyle, then anchored the Aussies to another world mark with a 400 freestyle relay win _ all in the same day Saturday. He finished second in the 200 freestyle Monday.

With Thorpe taking a few days off, the Aussies can focus their flag-waving, singing and cheering on Susie O'Neill, who won the 200 freestyle and was the leading qualifier for the 200 butterfly final Wednesday.

The Aussie team of Thorpe, Michael Klim, Todd Pearson and William Kirby won in 7 minutes, 7.05 seconds _ lowering Australia's world mark of 7:08.79 set in August 1999.

"I'd never thought we'd beat these guys but (coach Don Talbot) told us we could be the best in the world," Kirby said. "If not this time, it's going to be a really hard fight."

The U.S. team, comprised of Scott Goldblatt, Josh Davis, Jamie Rauch and Klete Keller, won the silver in 7:12.64.

"It was going to take a lot of miraculous swimming on each of our parts in order to be close to the Australians," Rauch said. "There hasn't really been a group of 200 men as good as that ever."

The Netherlands earned the bronze in 7:12.70.

Australia's record was the 11th world mark set or tied in four days at the Olympic pool.

Alan Thompson, the Australian team manager, said Thorpe might swim in the 400 medley relay preliminaries Friday.

"He's one of the options, but a lot of guys want to do it," he said. "If you swim a heat in a relay, you get a medal. It's worthwhile to do it. There's a lot of competition for a spot on the relay team."

Thorpe led off and gave the Aussies a two-body-length lead over the Americans after 200 meters. He failed, however, to break the world record in the 200 free set by Dutchman Pieter van den Hoogenband on Monday night, missing by nearly seven-tenths of a second.

The crowd of 17,500 at Sydney International Aquatic Center was at its loudest throughout the race, then sang along as the public address system blared Men at Work's hit "Down Under" afterward.

For the Americans, it was another defeat in a relay event they once dominated, winning in 10 of the last 12 Olympics, including the 1996 Atlanta Games.

"I'm so excited for the silver," said Davis, who won three relay golds four years ago. "To me, it's the most special medal in these games. Everyone swam their hearts out. I'm glad we had Klete on the end. He's a big up-and-comer."

The Dutch, anchored by Van den Hoogenband, won their first Olympic medal ever in the event.

In the 200 butterfly, Malchow, of St. Paul, Minn., was first in 1:55.35, bettering his own Olympic mark of 1:56.02 set in Monday's semifinals.

Cristina Teuscher of New Rochelle, N.Y., added to the Americans' haul with a bronze in the 200 individual medley. The United States has 14 medals in four days at the Olympic pool.

In the 200 butterfly, Denys Sylant'yev of Ukraine won silver in 1:55.76. Justin Norris of Australia took bronze in 1:56.17.

Michael Phelps of Baltimore, a 15-year-old who is the youngest male U.S. Olympic swimmer in 68 years, finished fifth in 1:56.50.

Malchow added gold to the silver he won in the same event in Atlanta, where at 19 he was the youngest man on the U.S. swimming team.

Always a strong finisher, Malchow wasn't worried when he was fifth at 50 meters, third at 100 meters and second to Norris at 150 meters.

"I stuck with my wits," he said. "When you're a competitive person, it's hard to sit back and watch people ahead of you, but you've got to pick your moments."

Having lowered his Olympic record in the prelims and again in the semis, Malchow fell 17 one-hundreths short of his world record of 1:55.18 set in June at a meet in Charlotte, N.C.

In the women's 200 individual medley, Yana Klochkova won her second gold of the games _ the first two in Ukraine's swimming history. She won in an Olympic record 2:10.68, breaking the 8-year-old mark of 2:11.65 set by Lin Li of China.

Beatrice Caslaru of Romania took silver in 2:12.57. She claimed bronze in the 400 IM, where Klochkova was the gold medalist Saturday.

Teuscher won bronze in 2:13.32.

"I'm happy I stuck it in there for a medal," she said. "You can't complain when you get a medal in the Olympics."

Gabrielle Rose of Memphis, Tenn., was seventh at 2:14.82, slower than the personal best of 2:14.40 that she swam in the semis.

Gary Hall Jr. of Phoenix, the silver medalist in Atlanta, made Wednesday's final by finishing sixth in 49.13. He called Van den Hoogenband's swim "absolutely amazing."

"I don't know if anyone can catch him," Hall said. "Anything can happen in an Olympic final. If you can get a ticket, you should be there."

O'Neill touched off a raucous celebration by winning the 200 freestyle. The crowd chanted "Susie, Susie" as O'Neill churned to the finish in 1:58.24.

"I tried not to listen because they were putting me off," O'Neill said. "I just closed my eyes and tried to swim my own race."

Martina Moravcova of Slovakia earned her second silver medal of these games in 1:58.32. She won silver in the 100 butterfly Sunday.

Claudia Poll of Costa Rica, the defending Olympic champion, settled for bronze in 1:58.81. She also won bronze in the 400 free Sunday. The United States failed to advance anyone to the final.

O'Neill barely had time to dry off before she returned for the 200 butterfly semis. The world record holder led eight qualifiers for the final in 2:07.57.

Misty Hyman of Phoenix was fourth in 2:07.96, while Kaitlin Sandeno of Lake Forest, Calif., was sixth in 2:09.40.

Domenico Fioravanti of Italy led eight men into the 200 breaststroke final, qualifying first in 2:12.37. Kyle Salyards of Lancaster, Pa., was third with a semifinal time of 2:13.38.

(Copyright 2000 by The Associated Press. All Rights Reserved.)