It is alleged that Watts, 24, Â punched a woman of the same age an apartment in Coogee, at around 4am on Sunday morning.
Police had not actually named Watts as being involved in the incident, but said:
“The man allegedly punched the woman to the face, before striking her numerous times to the back of the headâ€, police said in a statement.
It is also alleged that the woman was thrown into the couch, and suffered a blow to the head as a result.
The alleged assault left the woman with bruising and swelling to her left eye, and as a result, an apprehended violence order (AVO) has been taken out against Watts.
After being questioned at Maroubra Police Station by Police, Watts was charged with assault occasioning grievous bodily harm.
Watts declined to comment as he left the police station, with his lawyer and a club official protecting him from reporters trying to get answers out of him.
As a result of being charged, Watts will face Waverly Local Court on Thursday.
Stephen Alexander, Watts attorney, said that in light of the incident, and of Watts being charged, it would be inappropriate for him to comment on the matter.
Roosters boss Steve Noyce said that is still unknown if five-eighth Todd Carney was also present, drinking, despite attending Alcoholics Anonymous.
“I’m driving back from the Central Coast and will be investigating it further this afternoon,” Noyce said.