Former Confederation of African Football (Caf) president Issa Hayatou and secretary general Hicham El Amrani have been fined $27.9m each by the Egyptian Economic Court (EEC).
The EEC ruled that the pair flouted local Egyptian law when signing a billion-dollar deal between Caf and French media company Lagardere in 2015.
The deal was not open to free and fair tender as required by Egyptian law, the EEC claimed.
Hayatou and El Amrani will both appeal.
"This verdict is quite grotesque and has no justification in that it constitutes a flagrant disregard for the facts of the case and for the provisions of Egyptian and international competition law," Cameroon's Hayatou said in a statement.
"I will naturally appeal … while reserving the right to bring the case before any other competition international court, so as to put an end to this intolerable defamation and repeated attacks on my honour."
Hayatou, who maintains the case is politically-motivated, and Morocco's El Amrani both worked for many years for Caf, which is based in the Egyptian capital Cairo.
As such, Egyptian authorities maintain that Caf is governed by local laws.
Nonetheless, the EEC's ruling only sanctions Hayatou - who presided over Caf from 1988-2017 - and El Amrani, who also left his position last year.
"Mr El Amrani and I have, at all times, and in particular in relation to the agreement with Lagardere Sports, acted ex-officio and as mandated by the Caf Executive Committee, as evidenced by the successive deliberations and minutes," added Hayatou's statement.
"The decision of the Economic Court to condemn us while clearing Caf is in flagrant violation … of the Egyptian Competition Law, the individuals concerned and the entity represented being legally inseparable and jointly liable."
The sanction relates to a contract Caf signed with Lagardere in June 2015 about the broadcast rights for African football, including coverage of the flagship Africa Cup of Nations, between 2017 and 2028.
The original complaint was filed last year by the Egyptian Competition Authority, which asked Caf to cancel its contract and reopen it for tender after asserting the deal violated local anti-monopoly laws.
Caf responded at the time by stating that it did not sell any rights to Lagardere and had merely appointed the company as its marketing and media agent instead.
Lagardere paid $1bn for the privilege of finding buyers for the rights which 'remain vested at Caf', the football body said at the time.
"Despite the undeniable fact that the agreement between Caf and Lagardere is an agency agreement, the Economic Court insisted on qualifying it as a sales agreement," said Hayatou.
"This wrongful qualification goes against the provisions of the agreement and the documents submitted."
A statement issued by Lagardere Sports on Wednesday reiterated this stance.
"Upon reviewing the judgment, it is clear that it contains both material factual errors as well as fundamental misapplication of basic competition laws," the statement read.
"Our own legal advice with regard to our contract has remained clear and unequivocal and we continue to work with Caf in accordance with our contract to support the development of African football."
The BBC has contacted Caf for comment.