The World Anti-Doping Agency has been in touch with the Association of Tennis Professionals (ATP) over Andre Agassi's admission he took crystal meth in 1997.
"Our task is to protect the clean athletes and to make sure that these sorts of things don't recur," said Wada director general David Howman.
"If we didn't take any steps, somebody would be knocking on our door saying, 'Well, what are you doing about this?'"
Agassi's admission has raised questions about the ATP's governance of the game.
Agassi, who won eight Grand Slams and is one of only six men to win all four major titles, wrote in his soon-to-be-released autobiography that he took the highly addictive drug with a former assistant and then lied to the ATP that his drink had been accidently spiked.
The ATP believed his story and took no action against the Las Vegan, who at the time had slumped to 141 in the world rankings despite having three Grand Slam titles already under his belt.
The ATP has said it cannot comment on Agassi's drug-taking revelation because it had withdrawn its doping case against him.
Because Agassi took something from the banned list in 1997, the offence is outside of Wada's statute of limitations - the eight-year bar.
But Howman wants to explore whether there could be other avenues to bring charges against him.
"If he's lied, and he's confessed he lied, so he's obviously lied and he lied under oath then I think that warrants further investigation to see whether there might be any other charges," said Howman.
JONATHAN OVEREND'S BLOG" How many more, like Agassi, simply bluffed their way out and got away with it? "
"We all know about Marion Jones, she lied to a tribunal, it can't just be one of those things you get away with," he added in reference to the American sprinter who served a six-month prison term for lying to federal prosecutors about her drug use.
"The second issue is, he had a lawyer represent him, does his lawyer know that he was lying?
"Maybe something can be done in relation to that."
Howman also intends to make the International Tennis Federation aware of the Wada letter to the ATP.
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