Jack Hetherington is facing a week on the sidelines with an early guilty plea after being slapped with a Grade 2 contrary conduct charge.

Coming late during a horror loss for the Newcastle Knights to the Canterbury Bulldogs at Homebush, both Hetherington and Canterbury Bulldogs hooker Reed Mahoney were sin binned by referee Peter Gough after a brief push and shove in the middle of the park.

Accor Stadium
   Crowd: 17,784

Hetherington, who was sin binned first, amazingly waited in the tunnel for Mahoney to follow him instead of going into the dressing rooms.

The duo then had another push and shove, initiated by the Newcastle forward, with Bulldogs' team officials were quick to step in and separate the duo.

Coach Adam O'Brien admitted he had no idea about the altercation during his post-game press conference, but he certainly will now, with Hetherington to be suspended for one match with an early guilty plea, or two if he heads to the judiciary and loses the challenge at panel.

Mahoney was also charged, but his Grade 1 offence will see just a $1000 fine with an early guilty plea, or $1500 if he fights and loses.

Two other Bulldogs players were charged on Sunday, with Drew Hutchison cited for a Grade 1 tripping offence. A three-year incident-free record will see his fine reduced to $750 with an early guilty plea, or $1000 if he fights and loses.

Jaeman Salmon was also charged for a crusher tackle on Jackson Hastings and will face a $1000 fine with an early guilty plea or $1500 if he fights and loses.

No charges were made out of the Sharks and Cowboys clash later on Sunday.

PointsBet Stadium
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All four players have until midday (AEST) on Tuesday to determine if they will accept early guilty pleas or fight their charges at the judiciary.