Roger Huguet, the chief executive, and Fabio Tordin, another executive, were suspended, Imagina said in a statement.
Miami-based Media World was one of the unidentified sports marketing companies alleged in a U.S. indictment in May to have agreed to pay a bribe to a high-ranking football official in the Americas, sources told Reuters in July.
The U.S. Justice Department announced on Thursday that Huguet had pleaded guilty to charges of conspiracy to commit wire fraud and money-laundering.
Tordin, the former chief executive of Traffic Sports USA Inc., pleaded guilty to three counts of wire fraud conspiracy and one count of tax evasion, it said in a news release.
Both men agreed to forfeit more than $600,000 each as part of their pleas.
Along with other defendants, Huguet and Tordin could face up to 20 years in prison, and Tordin faces up to an additional five years for the tax charge, the Justice Department said.
Imagina said it was appointing new management at Media World and that Irantzu Díez Gamboa, previously director-general of Globomedia Group in Spain, had been named director-general of Imagina US.
FBI agents searched the Miami office of Media World on Thursday, a Reuters photojournalist said.
Imagina said it would cooperate fully with U.S. judicial authorities. "The group will do everything in its power to clarify the circumstances in which these events happened," its statement added.
Football bosses from across South and Central America were among 16 people charged on Thursday with multi-million-dollar bribery schemes for marketing and broadcast rights, in a dismantling of a Latin American football network by U.S. prosecutors.
(Reporting by Adrian Croft; Additional reporting by Jonathan Stempel in New York; Editing by Mark Potter)
