It is unclear what transpired, but newspaper reports suggest that 26-year-old Marshall was involved in a fight with another man in central Sydney in the early hours of this morning.
The club have released a statement confirming the news.
“Marshall has briefed the Club fully on all circumstances surrounding the incident and will co-operate fully with any police enquiries that may result from this matter.
“It would be inappropriate for the Club to make any further comment at this stage.”
The news is a huge blow for the NRL before the competition’s opening round next week – Marshall is a prominent face in the league’s 2011 promotional video.