Tennis authorities say they have a zero-tolerance approach to match-fixing but won't be reopening old files in the wake of sensational media reports.
A joint BBC-Buzzfeed investigation suggests players, including several at this month's Australian Open, are suspected of rigging matches and incidents during tennis matches, including at Wimbledon.
The report says a strong body of evidence was behind a referral of a core group of 16 men, including grand slam winners in the past decade, to the Tennis Integrity Unit (TIU) in 2008, but have faced no sanction.
Gambling syndicates in Russia and Italy are alleged to be behind the allegations. The report is based on a cache of leaked documents from an inquiry set up by the ATP in 2007 to look into claims of match fixing and suspicious gambling.
No players are named in the report.
Speaking at Melbourne Park while the first matches in the Australian Open were under way, ATP president Chris Kermode dismissed suggestions the sport didn't take match-fixing seriously.
"The Tennis Integrity Unit and the tennis authorities absolutely reject any suggestion that evidence of match fixing has been suppressed for any reason or isn't being thoroughly investigated," he said.
"All of us here in tennis are absolutely committed to stamp out any form of corrupt conduct in our sport.
"There is a zero-tolerance policy on this. We are not complacent. We are very vigilant." Kermode, joined by several tennis officials as part of a "united response" to the report, was not able to disprove the specific allegations.
"As the BuzzFeed report states itself, the investigators hit a brick wall and it just wasn't possible to determine who the guilty party was in relation to this match," he said.
"In its investigations, the Tennis Integrity Unit has to find evidence as opposed to information, suspicion, or hearsay."
TIU director Nigel Willerton said it would be inappropriate to disclose whether active players were the subject of current investigations.
Kermode told the BBC match-fixing in tennis was at an "incredibly small level" but $14 million had been invested in the issue.
"I think it will be seen that tennis is in a very, very good place and we are acting accordingly," he said.
BuzzFeed journalist Heidi Blake defended her report on ABC radio, saying tennis authorities had to be more transparent.
"In secret behind closed doors, [tennis authorities] looked at the files ... files full of evidence investigators themselves said was the strongest evidence they'd ever had," she said. "These are experienced betting, corruption and crime investigators.
"Tennis authorities looked at it and they decided not to investigate it further. I do think world tennis has some really serious questions to answer about why this evidence was under lock and key for so long."