SYDNEY, Australia (AP) -- A sixth gold medal for Jenny, a pair for "The Thorpedo," and world records all around. Swimming superstars old and new dominated the first full day of competition at the Sydney Olympics.

 But events took a tragic turn several hours later with the reported death of the wife of IOC president Juan Antonio Samaranch, who had left Sydney on Saturday to be with his gravely ill wife just hours after presiding over his final Olympic opening ceremony.

 At the Sydney International Aquatic Center, Jenny Thompson became the first American woman to win six Olympic golds Saturday, anchoring a U.S. women's 400-meter freestyle relay that set a world record of 3 minutes, 36.61 seconds. All her other golds have come in relays, too.

 Clearly thrilled, she tore off her cap and goggles after touching the wall.

 But the real hero to the 17,500 frenzied fans at the Olympic aquatic center was Australia's teen idol, Ian Thorpe: Three times he swam, three times he broke records.

 Thorpe set an Olympic mark in the prelims of the 400-meter freestyle and a world record in the final. Then he came back a few minutes later and anchored the men's 400 relay team, edging out the dogged American team and setting a world record of 3:13.67.

 Thorpe's teammate, Michael Klim, broke the individual world record for 100 meters on the first leg of the relay. The United States had never lost a men's 400 free relay in Olympic or world competition.

 Individually, Thorpe ripped through the finals of the 400 in 3:40.59, breaking the record of 3:41.33 he set in the same pool last May. Fans chanted "Thorpey! Thorpey!" Among those in the stands was Australian Prime Minister John Howard.

 "I really wanted to bring it home for the crowd tonight," Thorpe said.

 Yet another world record already had fallen by the time Thorpe got his: Yana Klochkova of Ukraine set in a new mark in the women's 400-meter individual medley, winning in 4:33.59 seconds.

 In the prelims Saturday, Thompson, and then the Netherland's Inge de Bruijn, had lowered the Olympic mark in the 100-meter butterfly.

 Thorpe's world marks seemed almost inevitable after he, too, set an Olympic record earlier in the day, egged on by his overheated fans.

 "I believe he's the best swimmer in the history of the world," American swimmer Josh Davis said.

 In Madrid, the state news agency Efe reported the death of Samaranch's wife, Maria Teresa Salisachs-Rowe, who was 67. A friend who answered the phone at the family home in Barcelona, confirmed the death but did not provide details or identify herself.

 Samaranch left Sydney earlier Saturday (Friday night EDT) to be with his wife in Barcelona, just hours after presiding at the opening of his final Olympics as International Olympic Committee president.

 IOC first vice president Dick Pound of Canada assumed the role of president in Samaranch's absence.