Melbourne  - A group of 65 sportsmen already challenged it before Belgian courts, but the new World Anti-Doping Code received a severe blow Wednesday from one of the biggest names in sport, tennis world number one Rafael Nadal.

The Spaniard is outraged about a rule that forces high-performance sportsmen to say where they are going to be for an hour each day, 365 days a year.

"I think it shows a lack of respect for privacy," Nadal said after qualifying for the semifinals of the Australian Open. "I think it's a disgrace, particularly knowing what our sport is like."

The new code from the World Anti-Doping Agency (WADA) went into force on January 1, and forces sportsmen identified by their international federations to inform the organization of their daily whereabouts every three months.

If a sportsperson cannot be found where they said they would be three times in an 18-month period, he or she is considered to have violated anti-doping regulations and is liable for sanctions.

"Even my mother or my uncle do not know where I am sometimes, so having to send a message or to be scared all day in case there is a last-minute change seems to me to be a complete exaggeration," Nadal warned.

He opted to designate the hotel where he stays during each tournament and 7 am as his contact details.

"That is the only time when I am sure I will be there," the player said.

He has already had a visit from anti-doping agents at his home on the Spanish island of Mallorca, at 8am on a Saturday. He had just had a night out with his friends.

"So you can imagine..."

"Those are things that completely have to change, and there is a unanimous voice on that in the locker room," said the Spaniard, who is also the vice president of the ATP players' council. "It is an intolerable hunt. We have proved that we are a clean sport. You can count (doping) cases with one hand."

The French Open and Wimbledon champion said he is ready to join "immediately" the group of 65 footballers, cyclists and volleyball players who are looking to fight the code at the courts. They appeal to the right to privacy that is upheld in the Belgian constitution and in the Council of Europe's European Convention on Human Rights and Fundamental Freedoms.

In case they win, their move could become a precedent that gets WADA into trouble.

"In the end we are humans and we do not have to feel like criminals just because we do sport," Nadal said.

WADA claims that recent changes in rules - which used to demand that sportsmen be available for tests in this way only out of season - were intended to make things easier for sportsmen. Now they are only required to report their location one hour per day, and not for the whole day.

Stuart Miller, the head of the anti-doping programme of the International Tennis Federation (ITF), said this should not be a problem.

"Except for the notion that if you provide information about your whereabouts on a quarterly basis, it's possible your plans might change," was quoted as saying in the daily USA Today.

In that case, he stressed, players can notify the relevant authorities by e-mail, text message or even fax.

Some tennis players, however, cannot quite get organized and say the last thing on their minds is telling anti-doping authorities about their whereabouts.

US doubles expert Mike Bryan has said he has already missed two dates and admitted that the possibility of a third is "a little scary."

Perhaps he should follow the advice of Kelly Wolf, an agent for the firm Octagon.

"You almost have to think of WADA as your mother, father, girlfriend and boyfriend," said Wolf.

However, Nadal, for one, has no intention of getting that close to the agency. dpa