BEIJING -- US swimming prodigy Michael Phelps broke the Olympic record in his first show in the Water Cube Saturday night, shaving 0.44 seconds off the previous record set by himself in Athens.

US swimmer Michael Phelps competes during the men's 400m individual medley swimming heat at the National Aquatics Center at the 2008 Beijing Olympic Games on August 9, 2008 in Beijing. Phelps placed first in the event.  [Agencies]

Phelps led all the way to the finish in the men's 400 individual medley, clocking 4:07.82, less than three seconds off his personal best.

"I am pretty surprised. I didn't think that I'd be the first to get it, not until the finals," Phelps said commenting on the new Olympic record. "I didn't expect the heats could be so fast. After seeing the first two heats, I just wanted to be the top seed for tomorrow."

Another U.S. swimmer, Ryan Lochte, who gained fame as the world's most consistent silver-medalist swimming against Phelps in his signature events, ranked fourth, following Hungarian Laszlo Cseh and Italian Luca Marin.

"If I's right there with him then that's pressure. We'll see what happens," Lochte said. Phelps holds the world record of the men's 400 individual medley.

Coming off a historic seven-win performance at last year's world championships, Phelps, who is to swim eight events in Bejing, is expected to break Mark Spitz's record of winning seven golds at one Games.

Phelps had the chance to break Spitz's record four years ago in Athens, where he competed in the same eight swimming events. However, with six gold medals and eight overall, he narrowly missed out.

The final race will be held tomorrow morning.