Former sprinter Frankie Fredericks said on Monday he had stepped down from an IAAF taskforce investigating Russian doping amid a corruption probe.
"I have decided to step aside from the taskforce so that the integrity of its work is not questioned due to the allegations made against me in Le Monde," the 49-year-old Namibian was quoted as saying in an IAAF statement.
"It is important that the taskforce's mission is seen as free and fair with no outside influence."
Le Monde newspaper on Friday said that Fredericks, a four-time Olympic silver medallist, received nearly $300,000 (283,000 euros) from a figure accused of corruption in international sports on the day Rio won the bid to host the Games.
IAAF president Sebastian Coe has appointed Slovenian former high-jumper Rozle Prezelj to replace Fredericks on the taskforce.
Le Monde claimed Fredericks received a payment from the Pamodzi Sports Consulting firm owned by Papa Massata Diack, who alongside his father and former IAAF chief Lamine Diack faces bribery charges in France over millions of dollars paid to cover up doping failures by Russian athletes.
French investigators are also looking into the possibility that bribes were paid over the awarding of the 2016 Olympic Games to Rio, Le Monde said.
Three days before the IOC awarded the Games to Rio on October 2, 2009, Brazilian businessman Arthur Cesar Menezes Soares Filho paid $1.5 million to Papa Massata Diack.
Another payment of $500,000 was made around the same time to another account belonging Papa Massata Diack in Russia.
When the Le Monde story broke, Fredericks's defence was taken up by the International Olympic Committee.
IOC spokesman Mark Adams said Fredericks had "emphasised his innocence" over the payment and claimed it related to "a marketing contract with Pamodzi Sports Consulting running from 2007 to 2011".