It will be a one-day event to be held at the Wade Park in Yenda on Sunday, March 22 and hosted by Waratahs in a knockout format instead of the round-robin which has been used in previous years.

"It will be a proper knockout this year," Group 20 president Mark Stenhouse said.

"It will be one loss and you go home for the 16s, 18s, league tag and first grade."

Stenhouse said the changes to the format were made to try and help the clubs with the season proper starting two weeks later.

"It isn't so much to do with ground availability, it's more to do with the clubs," he said.

"It takes the pressure off the clubs to have their players ready for a knockout split across two weeks if you do well in the first week.

"There is no prize money on offer for the lower grades, and it can be a bit of a hassle for the younger grades to have to back up the next week."

The knockout isn't the only aspect which has changed the offseason with changes being made to the rules around concussion which have been set out by New South Wales Rugby League.

The NSWRL will introduce new concussion protocols into all its competitions this season, including an 18th man concussion substitution and a mandatory stand-down period of 14 days, in the interests of player welfare and safety.

NSWRL general manager of football Barrie-Jon Mather said the decision was made in the off-season following a comprehensive review of concussion policies and procedures.

"We are just trying to increase the level of care and err on the side of caution when it comes to head knocks and concussions," Mather said.

"All sports have taken their guidance from the same experts and the same studies and the NSWRL is doing what they can in the interests of player welfare and safety."

The changes this year will include the introduction of an 18th man concussion substitution, which will allow clubs to carry an additional player on the bench who may be substituted into a game only if another player is ruled out from concussion.

Players who are concussed will also be required to stand down for a period of 14 days and will only be eligible to resume contact training and be considered for selection again after receiving clearance from a specialised concussion doctor.

Stenhouse welcomed the changes to the rules around concussion and felt like they were probably long overdue.

"We don't want to see guys going down a couple of weeks after an incident because of concussion, so we are all for the change," he said.

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