Roger Federer, Andy Murray and Rafael Nadal have called for improvements to tennis' anti-doping program following the recent drug controversies in athletics.
A WADA report released this week declared systemic, "state-sponsored" doping in the Russian athletics program, upholding previous media revelations. Those discoveries were preceded by news of police investigation into a former IAAF president amid allegations of bribery and cover-ups.
Asked if the WADA conclusions surprised him, Federer said, "No. But then it says there are other nations that are not doing it properly either."
Federer called once again for increased testing, as he has done in recent years when the issue has been raised, saying it was essential during the final few rounds of tournaments. "I'm always surprised when I walk off court after a final and I'm like 'where is anti-doping?'" he said. "Whenever you make the quarterfinals of a tournament, when the points are greater, the money is greater, you should know that you will be tested.
"It's very important. Players need to feel that they're going to be tested, so they will shy away from any stupid thought they might have."
The 17-time Grand Slam champion would also like to see the program become bigger and better.
"They are trying their most but we can do more," said Federer, "There needs to be more resources."
"And if they keep the tests for longer, I'm all for that, not just weeks and months, years I'm talking about. That's the way to scare people."
Murray, who along with Federer has been vocal about increasing anti-doping efforts, added that increasing the amount of tests alone was not enough.
"This year I've been tested more than ever before, the most in my career this year. But it's getting to the stage where that doesn't matter anymore," Murray said. "I've been tested more than any athlete but it doesn't make a difference. Lance Armstrong was the most tested athlete on earth and didn't fail a drug test. That doesn't necessarily guarantee anything."
With the athletics scandal centering on falsified information and corruption at the official levels, Murray emphasized that ensuring proper procedure in the running of the program was also important.
"Prize money now is so high, there's no reason not to have as perfect a process as possible," he said. "I think the more transparency the better, there's absolutely no question about that."
The tennis anti-doping program, administered by the ITF, is estimated to spend about $4 million a year, based on contributions from the ATP, WTA, ITF and Grand Slams.
Nadal said he would like all test results to be released publicly, and said he would not object to improvements being financed from prize money amounts.
"Will be great if one day the anti-doping that we do is 100 percent public?" said the Spaniard. "I don't care if we have to put prize money, fine for me."
Nadal joined the call for measures to maintain a secure program. "Without being arrogant, it's a rich sport, we have a very healthy sport, the people who run the sport need to be sure sport is clean," he added. "Players need to be sure and confident with people who run the sport to be 100 percent clean in the right way."
The players were speaking to media before their participation in the ATP World Tour Finals.