- Rafael Nadal wants stricter drug controls in tennis
- Sport has been hit by several drug scandals in recent months
- ITF has introduced a biological passport program to battle the problem
- Czech tennis player banned for six months after positive test for sibutramine
Rafael Nadal has called for stricter doping controls and more transparency to help eradicate drug cheating in tennis.
Nadal wants to ensure tennis is not plagued by the doping problems which have affected so many other sports, notably cycling, following the Lance Armstrong saga.
"It's something even I don't like to talk about because it has damaged the image of sport, and sport doesn't deserve this kind of thing in my opinion," the 11-time grand slam champion told CNN's Open Court show before his weekend triumph at Indian Wells.
"When somebody like Armstrong was an idol for most of the people who loved sport, at the end, you see that was not true.
"It's a big disappointment, so I think we need to work together in the same direction to change the situation. It cannot continue like this.
"We need to be stricter on a few things. We need to have all the controls made public."
Nadal, who made his return to action in February following a seven-month absence with a knee injury, said tennis needs an all-encompassing approach to drug testing in order to maintain the sport's image.
"We have to work together, we have to be working together with the administrators and hopefully we can change that terrible situation," he said.
"We are lucky that in tennis, it has happened in just very exceptional cases but at the end, tennis is in sport, so if that happens in other sports, it affects tennis too."
In recent months sport has been hit by several high-profile doping scandals.
Cyclist Armstrong was stripped of his seven Tour de France titles, while Australian sport was given a wake-up call after a government report alleged athletes were using illegal substances supplied by organized criminal groups.
Football's governing body FIFA has already stated its intention to introduce biological passports, while the outcome of the Operation Puerto trial in Spain into the relationship between sport and doctor Eufemiano Fuentes' doping network is ongoing.
The International Tennis Federation (ITF) recently confirmed that it will introduce a biological passport program, a system similar to the one used in cycling, where players' drug test results are kept over a long period of time so that the use of illegal substances is more easily detected.
"The implementation of the athlete biological passport is an important step in the evolution of the tennis anti-doping program as it provides us with a great tool in the fight against doping in our sport," said ITF President Francesco Ricci Bitti.
In 2011 the ITF and the World Anti-Doping Agency conducted just 21 out-of-competition blood tests in a bid to detect illegal products such as human growth hormone (HGH), EPO, transfusions and other blood-doping substances.
According to the latest figures, the vast majority of tests in tennis in 2011 -- 2,019 of a total of 2,150 -- were urine.
In February, the ITF banned Czech Republic player Barbora Zahlavova Strycova for six months after she tested positive for the stimulant sibutramine at a tournament in October.
She insisted the drug had made it into her system through a supplement and denied taking it to enhance her performance.
In 2010, former top 100 player Wayne Odesnik, was suspended by the ITF after Australian customs officials found eight vials containing HGH in his luggage.
He denied using HGH and never tested positive for it.
His two-year ban was cut in half because the ITF said Odesnik cooperated with its anti-doping program.
Earlier this month, 17-time grand slam champion Roger Federer told CNN that it was "naïve" to think tennis is clean, while world No. 1 Novak Djokovic recently queried the declining number of blood tests he had undergone.
"I wasn't tested with blood for the last six or seven months," he told reporters. "It was more regularly in the last two, three years ago. I don't know the reason why they stopped it."