Fainu was charged on Tuesday after handing himself in at Liverpool Police Station and was denied bail over the incident. He is due to face court on Tuesday afternoon.
The 21-year-old Sea Eagles hooker was charged with "wound person with intent to cause grievous bodily harm, affray and recklessly cause grievous bodily harm in company," according to a NSW Police Media statement on Tuesday.
In their statement, NSW Police Media added: "Police will allege in court that the man was involved in an altercation when he produced a knife and stabbed another man."
