Lausanne: The International Olympic Committee (IOC) said on Wednesday it had handed "severe reprimands" to three boxers for betting on fights at the Rio Games, two of them Irish.
Michael Conlan, Steven Donnelly and Britain's Anthony Fowler — cousin of the former Liverpool and England footballer Robbie Fowler — breached rules introduced for the Games in August.
Donnelly was found to have made two bets on himself to lose one of his bouts — which he later won so did not win any money.
"Participants at the Olympic Games are not permitted to bet on Olympic events and are obliged to report any approach or suspicion of manipulation," the IOC said in a statement.
Bantamweight Conlan, 24, welterweight Donnelly, 28, and middleweight Fowler, 25, must now all prove they have successfully followed the IOC's educational programme if they want to fight at Tokyo 2020.
The punishments were not harsher because "there was no intent to manipulate any event", the IOC said.
The IOC also dished out a reprimand to the Olympic Council of Ireland and the British Olympic Association for not properly informing their athletes about the rules relating to gambling.
Conlan, an amateur world champion, was at the centre of a separate controversy in Rio after suffering a surprise unanimous points decision defeat to Russian Vladimir Nikitin, when most observers felt he won.
A seething Conlan, strongly fancied for a medal, made an obscene gesture to judges in protest before storming off.