North Queensland have been served with a breach notice carrying a $2000 fine following a verbal altercation between Cowboys trainer Billy Johnstone and a sideline official.

Johnstone allegedly made threatening comments towards touch judge Luke Potter during Saturday night's 23-16 NRL loss to Wests Tigers at Dairy Farmers Stadium.

The club has been given five business days to contest the breach notice, the incident adding to the mounting cost of the narrow loss.

From that game the Cowboys lost skipper Johnathan Thurston and hooker Aaron Payne to injury, while backrower Luke O'Donnell was banned for three matches following a grapple tackle.

Brought to you by AAP © 2024 AAP