CHINA'S swimmers have yet to decide which swimsuits they will wear just days before Olympic competition begins. The Nike-sponsored Chinese team was given permission last week to choose between its sponsor's product and the Speedo LZR Racer, which has figured in most of this year's world records.

Australian coach Denis Cotterell, who is working with the Chinese team and is guiding its best freestyle prospect Zhang Lin, said the Chinese swimmers were in a quandary because they would not be able to get custom-fitted Speedo suits and would have to rely on the generic sizes if they chose that brand.

The fit of the Speedo suit is extremely important to its effectiveness.

"We don't know what suit (Zhang) will be wearing, Nike is his sponsor and he only has access to the generic LZR because the Speedo people only arrived here a couple of days ago,'' Cotterell, who guided Grant Hackett to his first two Olympic gold medals in the 1500m freestyle, said.

Cotterell began working with Lin eight months ago and the swimmer's progress has been so striking that his coach was given a rare invitation inside the cloisters of the Chinese national team.

He joined the team a week ago, as did fellow Australian coach Otto Sonnleitner, who is working in China for a university team, and has been drafted into the Olympic preparation to advise on starts and turns.

They are closeted with the swimming team and other stars such as basketball's Yao Ming and hurdler Liu Xiang, amid tight security in central Beijing, guarded around the clock by the People's Liberation Army.

There are five Australians inside the camp. Former national women's basketball coach Tom Maher, his wife, former Olympic player Robyn Maher, and fellow basketball team-mate Michele Timms, are all working with the Chinese women's team.

"It's like being in the institute (Australian Institute of Sport),'' Cotterell said.

"They have a lot of people in support, sports scientists, a lot of people to help, which can be pesky when you don't understand the language, but they are being unbelievably accommodating.

"They fill my fridge with beer because they know I'm an Australian.''

That alone is a big change from the Australian team, which runs a dry camp for both athletes and staff.

"It's a very casual atmosphere. They do play the national anthem every Monday morning and line everyone up facing the flag, but otherwise it's very casual,'' Cotterell said.

"We train when we want to, we generally go in before the rest of the team to get clearer water.''

The Chinese team, the biggest squad competing at the Olympics with 46 swimmers, appeared at the Water Cube yesterday and conducted a series of time trials to decide on relay positions.

The home team has few medal prospects in the pool beyond 200m butterfly specialist Wu Peng, the silver medallist behind American world record-holder Michael Phelps at last year's world titles.

But Zhang has made strong progress after missing the world championships final last year, and is now ranked seventh in the 400m freestyle (3min44.97sec) and 10th in the 1500m (14:55.98).

Cotterell said he hoped to get Zhang into the 400m freestyle final, where he will probably meet Hackett and the young Korean world champion Park Tae-Hwan. After Hackett left Cotterell 18 months ago to move to Melbourne, both Park and Zhang sought the renowned distance coach's assistance.

However, Cotterell knocked Park back because he did not want to help someone beat the Australian champion he had nurtured since he was a child.

But more recently, Cotterell said he had "faith'' in Hackett's ability to prevail.

Park, 18, also swam in the Olympic pool for the first time yesterday as he prepared to face the veteran Hackett, who is looking to win his first gold medal in this event after finishing second to Ian Thorpe in Athens.

"He's in good shape and he feels confident to compete,'' Park's coach Roh Minsang said.

Hackett will present a far different prospect in Beijing than he did at last year's world titles, where he finished third behind Park while competing overweight and out of shape.

The Australian captain is back in peak fitness and itching to prove it at the Olympics.