Further details of alleged shortcomings at the Rio de Janeiro doping control laboratory - whose accreditation was revoked last year by the World Anti-Doping Agency (WADA) in a hugely embarrassing blow for Brazilian authorities - have emerged in minutes of a WADA meeting in South Africa now available on the agency's website.
The record of a WADA Executive Committee meeting held in Johannesburg last November asserts that three "false positive cases" had been discovered to have occurred prior to the revocation of its accreditation.
The assertion, included in a wide-ranging report by WADA director general David Howman, notes that all the cases had been in football.
The new information was said to have "complicated the reaccreditation process".
In May, Barcelona and Chelsea star Deco was cleared of a doping offence by the Court of Arbitration for Sport after they ruled his test at the laboratory in Rio de Janeiro had been mishandled.
The case against Deco, who retired last year due to injury, collapsed when his samples were re-tested in Lausanne, Switzerland.
WADA's revocation of the accreditation of the so-called Ladetec laboratory obliged football governing body FIFA to send samples from the recent World Cup in Brazil across the Atlantic for analysis in the Olympic capital of Lausanne at an additional cost of $250,000 (£148,000/€186,000).
New premises for the laboratory, whose services would ideally be required for the Rio 2016 Olympic and Paralympic Games, have been under construction.
But WADA President Sir Craig Reedie said in April that the new laboratory would be merely the start of a solution, with proper equipment, appropriate personnel and certain standards also being vital before accreditation could be reinstated.
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April 2014: Exclusive: FIFA decision to send World Cup doping samples to Switzerland will cost $250,000
April 2014: It's going to be difficult to replicate London 2012 anti-doping operation in Rio, warns WADA President
March 2014: Exclusive: Anti-doping lab will be "ready before end of next year", claim Rio 2016
March 2014: Exclusive: Rio anti-doping lab must "act quickly" to be ready for 2016 Olympics, says WADA's Howman