The photograph of Monaghan, a NSW and Australian representative, was allegedly taken during Canberra’s Mad Monday festivities.
“It’s very disappointing; he appears to have been subjected to a bit of tomfoolery by some teammates,” said Monaghan’s manager, Jim Banaghan.
“One of his teammates has taken a picture of it and it’s been passed around.
“I believe everyone involved is disappointed in what they have done.
“I’m working with [Raiders CEO] Don Furner to get to the bottom of it all.”