MICHAEL Phelps has begun his quest for eight Olympic gold medals in Beijing in impressive style, taking the men's 400m individual medley in a world record time of 4min3.84sec
Phelps's record was one of two set in the first swimming finals session of the Games, with Australia's Stephanie Rice also swimming a world record time and winning gold in the women's 400m IM.
With US President George W. Bush looking on, Phelps outdueled Hungarian Laszlo Cseh and fellow American Ryan Lochte to win in 4min 03.84sec - slicing 1.41sec off the previous world mark of 4:05.25 he set at the US trials in June.
"That was a pretty emotional race today," said Phelps, the subject of intense scrutiny for months as he readied his assault on US swimmer Mark Spitz's record of seven gold medals at one Games, set in Munich in 1972.
Phelps was unable to match Spitz's feat in Athens four years ago, winning six golds and two bronze. But he raised expectations that he could go even one better in Beijing when he won seven titles at the world championships in Melbourne last year.
To do so, he'll have to swim at least 17 times over the nine days of competition as he goes for gold in five individual events and three relays.
"I think I am as prepared as I can be at the moment, and this is the best time to be in that position," Phelps said.
"I can't express how excited I am to be able to start off with that event and how it turned out.''
With his medley triumph, Phelps, wearing the revolutionary Speedo LZR Racer suit, successfully defended one of his Athens titles.
On Sunday evening he was due to swim heats of the 200m freestyle, in which he finished third in Athens but has since claimed the world record. He said the frenetic pace of his programme didn't leave time to dwell on his success.
"I have to put it behind me," Phelps said.
"Act like it never happened. Because I have so many tough races ahead of me and so many hard opponents."
Phelps singled out Park Tae-Hwan, who triumphed in the men's 400m freestyle to give South Korea it's first Olympic swimming gold.
"Seeing Tae-Hwan go so fast in the 400m freestyle, I can't afford to relax," Phelps said.
Phelps turned in a blistering opening butterfly leg, surrendered the lead to Lochte at the first backstroke turn, and regained a narrow margin heading into the breaststroke.
Lochte, swimming two lanes over, briefly edged ahead in the breaststroke, but Phelps held the advantage at every remaining turn, closing out his rivals with a majestic finishing freestyle.
The Day 2 swimming was covered live on Beijing Now. See how it unfolded below.
Michael Phelps in early 2008 In Beijing, China at the 2008 Summer Olympics, American Swimmer Michael Phelps has won the gold medal for the U.S. Team in the 400 individual medley swimming event. 

Phelps clocked in at 4:03.84 managing to break his previous best time of 4:05.25 by almost 2 seconds, and setting a new world record in the event. This was his first gold medal won in the 2008 games. Phelps will swim the men's 4x100m freestyle relay tomorrow in an attempt to win his second gold medal.

Laszlo Cseh from Hungary came in second and received the silver medal, while Ryan Lochte from the U.S. came in third to win bronze.