St George Illawarra Dragons are investigating veteran centre Dane Nielsen for an incident which the club says went against their code of conduct.
The Dragons confirmed in a statement on Tuesday they had chosen not to name Nielsen for either first grade or the NSW Cup side this week for going against the club's code.
"Dane Nielsen has not been named in any team this week due to a breach of the club's code of conduct and the NRL Integrity Unit has been informed," the club said, as it announced its round four teams.
Speculation continued on Tuesday night that Nielsen had been involved in an incident with a player from a rival NRL club over the weekend.
The NRL's Integrity Unit has been informed of the incident.
A spokesman said the governing body would leave it up to St George Illawarra to investigate the matter internally.
The integrity unit will only step in and take over the investigation if it is not satisfied Nielsen has been properly dealt with.
It comes the day after news broke of a violent brawl involving Bulldogs recruit Jacob Loko and Manly winger Jorge Taufua outside a Sydney club on Saturday night.
Nielsen signed a two-year contract with the Dragons during the off-season and debuted for the club against Melbourne a fortnight ago.
He scored the club's only try against Wests Tigers a week later, only to be dropped for the trip to Canberra to allow room for exciting young talent Euan Aitken.
Nielsen chose not to play for the club's reserve grade as he took a week off to recover from soreness.
He has previously won an NRL premiership and World Club Challenge with the Storm.
Nielsen spent two seasons with the Warriors before joining the Dragons.
He has represented both Queensland and Indigenous All Stars during an eight-year career.
