Tennis is paying the price for being an Olympic sport and its new dope testing regime treats players like criminals, world number one Rafa Nadal says.
The Spaniard is leading criticism against the procedure adopted by the Association of Tennis Professionals (ATP), who signed the World Anti-Doping agency (WADA) protocol last year.
"It is not fair to have persecution like that," Nadal told reporters at the World Indoor Tournament in Rotterdam.
From the start of this year, players ranked in the top 50 must nominate one hour daily when they will be available for testing, as per WADA regulations.
However, Nadal, Briton Andy Murray and Gilles Simon say it is harassment of tennis players.
"They make you feel like a criminal," Nadal said. "Not even my mother knows where I am every day. It is very difficult to know where you are going to be tomorrow especially in a sport like tennis."
The tighter dope control is a result of tennis being an Olympic sport, but Nadal wonders if it is worth it.
"Sure we want to be an Olympic sport, but I think we don't want to pay a price like this for an Olympic sport," he said. "I am the first one who wants a fair competition, completely clean competition for everybody but the forms can be totally different."
French world number eight Simon almost missed an out-of-competition test while at home in Paris.
"I rescheduled a training session at Roland Garros and went to the zoo with my girlfriend, but I was called by the controller and just returned in time," he told Reuters.
Briton Murray hoped the testing could be simplified.
"I just wish that the out-of-competition testing was done in the off-season and then they just test us at every single tournament," he told a news conference.
"Then that's fine, we could get tested 30 times a year. I think that's enough to know whether someone's trying to cheat or not."
If a player misses three tests in 18 months they could face a two-year ban.
Murray and Simon felt tennis could not be compared with other sports as it involved constant travel.
"You have to fill in a three-month form, but if you are knocked out in a tournament and decide to travel the next day, you have to change it immediately," said Simon.
A player tested after his final match in a tournament can return home the next day and face an out-of-competition test, like happened to Murray after the Australian Open.
"I got a visit at 7am, hours after I came back from Australia. I woke up not really knowing where I was," he said.
"There has to be a more realistic and practical way to deal with the problem with tennis players."