Seoul: FIFA presidential hopeful Chung Mong-Joon accused Sepp Blatter of trying to smear him via the body's ethics committee, in a bid to force the South Korean to drop his candidacy.
Chung said the committee had launched an "unfair" hearing to suspend him for up to 19 years, at the behest of FIFA's scandal-hit president.
The investigation is based on alleged vote-trading and other wrongdoings related to bids for the 2018 and 2022 World Cup.
"People say FIFA's Ethics Committee is Mr. Blatter's 'hitman'. They never hit him but only those who challenge Mr.
Blatter," Chung told reporters.
He said he was under scrutiny for letters he sent in 2010 to FIFA executive members about the creation of a Global Football Fund (GFF).
South Korea proposed the fund to support football projects, valued at USD 777 million, as it was bidding to host the World Cup.
"No money or personal favours were exchanged in relation to GFF," Chung said, adding FIFA had closed the case in 2010 with no charges made against him.
That closed case has now been revived and could see him suspended for 15 years along with additional four years for defaming the committee, Chung said.
"The fundamental reason why I am being targeted is that I aimed straight at the existing power structure of FIFA," he said.
Such a "retroactive sanction" sought by the committee is based only on testimonies from Blatter and his former right-hand man, secretary general Jerome Valcke.
Valcke himself was suspended over allegations that he was aware of a black market ticket scheme surrounding the 2014 World Cup, though he has denied the claims.
Chung refused to present himself to the hearing unless Blatter and Valcke come together as witnesses.
The crisis of world football began in May, when nine FIFA officials and five sports marketing executives were charged by the US Justice Department over bribery worth more than 150 million dating back to 1991.
UEFA president Michel Platini had been the favourite to take over, but Chung is another leading candidate along with Prince Ali bin al Hussein, a former FIFA vice president from Jordan.
Chung has said that if elected he will stand for only one term to carry out reforms.