The British Boxing Board of Control has fined Chris Eubank Jr. £10,000 ($14,000) for misuse of social media.
Eubank appeared before the board last week for allegedly using a sauna to cut weight before his fight against Conor Benn in April.
Video posted on social media appeared to show Eubank using a sauna to make the 160-pound middleweight limit before the bout.
Eubank beat Benn on points, but was taken to a hospital afterward as a precaution.
Though he was not fined for using a sauna, which is prohibited by the board, he was fined for misuse of social media.
"Mr. Eubank Jnr. was found to be in breach of Regulation 25 for misuse of social media," the BBBC's Southern Area Council said in a statement this week.
"The Southern Area Council fined Mr. Eubank Jnr. the sum of £10,000.
"Mr. Eubank Jnr. was confirmed as arriving late for the official weigh-in ceremony for the contest in question and received a severe reprimand placed on his file from the Southern Area Council."
Eubank was fined previously for missing weight prior to the fight, having weighed in at 160.2 pounds on his first attempt and at 160.05 on his second the day before the fight. He was fined £375,000.
He did, however, stay within the 10-pound rehydration limit on the day of the bout.
Eubank and Benn will face off again Sept. 20 in London at a venue still be decided.