While everyone else wants to talk about the American swimmer's bid to win eight gold medals at Athens, Phelps has been conspicuously quiet on the subject.

Despite being grilled on the issue at a news conference on Wednesday, Phelps declined to discuss his prospects, repeating the sportsman's mantra that he is taking it one race at a time.

"My goal is to win one gold medal and then go on from there. That's my goal right now," Phelps said.

Phelps may well be satisfied to win a single gold medal but the promise of $1 million bonus if he can beat or equal the seven gold medals Mark Spitz won at the 1972 Munich Olympics serves as a constant incentive to strive for more.

It is a record that many consider will never be broken and the last man to even make an attempt was American Matt Biondi, who won five golds, a silver and a bronze at Seoul in 1988.

Spitz won four individual and three relay gold medals at Munich, all in world record time, but Phelps has entered five individual events in Athens and hopes to swim the three relays.

Phelps qualified for six events in Athens but dropped the 200 metres backstroke, where he finished second to Aaron Piersol at the U.S. trials, to concentrate on the 200 freestyle, 100 and 200 butterfly and the 200 and 400 individual medleys.

He also qualified for the 4x200 freestyle relay but is relying on the American coaches to decide whether to contest the other two relays.

SYDNEY BREAKTHROUGH

Phelps, who started swimming at the age of five, showed the first real sign of the potential he had in 2000.

He qualified for Sydney at 15, becoming the youngest man to represent the United States in swimming at an Olympics.

Phelps finished fifth in the 200 butterfly in Sydney but six months later broke the world record in the event, becoming the youngest man to hold a world record.

Later that year, he lowered the record further to win his first world title and has been riding a wave of success ever since, smashing world records and winning a stack of gold medals that have made him the number one swimmer in the world.

"I was disappointed not to win a medal at Sydney so I started training for Athens the day after it ended," he said.

Despite his phenomenal success, Phelps' chances of winning all eight golds remain slim. Bookmakers offer odds of 25-1.

He is a strong favourite to win the medley double and the 200 butterfly, events in which he holds the world record, but things get harder after that.

Australia's Ian Thorpe, who also entertained thoughts of tackling Spitz's record before settling for six events, is favourite to win the 200 freestyle.

Thorpe's world record is almost two seconds better than Phelps' best time for the event.

The race will also include defending Olympic champion Pieter van den Hoogenband and former world record holder Grant Hackett.

The Australians are favourites to win the 4x200 freestyle relay, an event in which they are reigning Olympic and world champions and world record holders.

Phelps also faces challenges from within his own team with compatriot Ian Crocker the favourite to win the 100 butterfly after winning the world title last year then lowering his world record and beating Phelps at the U.S. Olympic trials.

The 100 butterfly looms as possibly Phelps' most crucial event as he needs to win the race to be guaranteed a start in the medley relay.

Reluctant to talk about his chances, Phelps is adamant on one score: "It's not impossible, nothing's impossible."