Spain's Rafael Nadal called on the International Tennis Federation to conduct anti-doping blood tests and regularly publish the results to ensure the sport is clean.

"It's an important issue and I think it's better like that. It's better to publish (the tests)" to dispel rumors about who did or did not pass doping controls, Nadal said in a press conference at the Mexican Open in the Pacific resort city of Acapulco.

"They need to be made public so the people know who passed or who didn't pass" the tests, the 11-time Grand Slam champion said.

With his remarks, the Spaniard joined a chorus of voices calling for a greater effort to catch drug cheats.

Over the past several months, Serbian world No. 1 Novak Djokovic, world No. 2 Roger Federer of Switzerland and world No. 3 Andy Murray of Scotland have criticized the ITF for a lack of sufficient doping controls in recent years.

"It think it's (necessary) today with all the problems there have been with this subject and after the uproar over the case of (disgraced cyclist Lance) Armstrong. And we all have to make an effort so the sport is transparent," the world No. 5 said.

Nadal, who was off the ATP World Tour for seven months due to a knee injury and began his comeback early this month in Latin America, said tennis "is very transparent and very clean" because the doping cases that have arisen "have been very few and far between."

The Spaniard, who advanced to the quarterfinals of the Mexican Open with a 6-0, 6-4 victory Wednesday over Argentina's Martin Alund, said it is a "priority to conduct all the controls that are necessary and people must be informed about these controls." EFE