The Bulldogs have been hit with a $25,000 suspended fine after club legend Terry Lamb breached biosecurity protocols at a training session.
Lamb apologised to the club on Friday, but that didn't stop the NRL from issuing a breach notice on Friday night.
Acting NRL CEO Andrew Abdo acknowledged the proactive approach taken by Canterbury.
"Our biosecurity protocols are stricter than current government health orders to ensure the health and safety of all players and staff in our ecosystem," Abdo said.
"The rules must be complied with at all times to protect the competition."
The NRL was satisfied that the breach was inadvertent, and that the club has committed to improve its compliance with the protocols.
Lamb breached NRL protocols by shaking hands with several Bulldogs players before training on Thursday.
Players had been told to stay away from the club's training base on Friday due to Lamb's breach of COVID-19 protocols.
"I would like to apologise to the Bulldogs and the NRL for breaching COVID protocols at training yesterday," Lamb said.
"I was over excited about getting to Belmore again and wanting to wish Kieran [Foran] all the best for his 200th game and in doing so I breached the protocols by shaking the hands of several players to wish them all the best.
"Although I was not standing in the restricted zone, I shouldn't have contacted players in the bubble, but in my over excitement I overstepped the mark and I apologise for that.
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"I immediately went and got a COVID test and have been given a clean bill of health."
Bulldogs CEO Andrew Hill said the club had worked hard to adhere to all NRL protocols around getting the game restarted "and we acknowledge the tremendous work that has gone on to get us playing again".
"Yesterday's breach was a case of Terry making a mistake in trying to wish players all the best and breaking the protocols set out around the bubble," Hill said.
"We acted swiftly to inform the NRL and to get Terry tested straight away and with his results showing a clean bill of health, we will now revise our processes to make sure that this never happens again."
Lamb was filmed by Channel 9 shaking hands with Foran, Will Hopoate, Dallin Watene-Zelezniak and Brandon Wakeham.
Lamb is not a member of the 50-person list the club is allowed to interact with the team at training or matches.