Castleford Tigers have disciplined full-back Richard Owen but refused to reveal his indiscretion or punishment.
The club say the 21-year-old accepted he had committed a serious breach of the club's code of conduct.
He said in a club statement: "My punishment is deserved; I have learned my lessons and will make sure this never happens again.
"I'm even more focused now on restoring the faith the club have in me and will do all I can to make a big impact."
The statement added: "The club is also aware of a recent incident involving the player that is the subject of other investigations. This matter will be considered by the club, if required, when the appropriate authorities have determined this issue."