he NRL has reiterated its desire to keep players safe, saying it will "impose heavy penalties" and may bring in further measures to ensure teams adhere to concussion rules.There have been a number of incidents through the first three weeks of the season of players not staying off the field despite what appeared to be clear concussions.
On Saturday afternoon, Parramatta hooker Nathan Peats was flattened after his head collided with the shoulder of rampaging Warriors prop Jacob Lillyman.
He was taken off for a concussion test but came back on to play out the rest of the game.
There was a similar case involving South Sydney half-back Adam Reynolds in round two.
Reynolds was left dazed after a tackle on Roosters back rower Aidan Guerra but returned just over 10 minutes later after apparently passing the concussion test mandated by the NRL last year and eventually led the premiers to a thrilling 34-26 win.
The Rabbitohs' medical team also copped criticism from some corners last year for allowing Clive Churchill medallist Sam Burgess play on with a broken cheekbone sustained in the first tackle of Souths' 2014 grand final victory.
On the other side of the coin are the Broncos who lost star prop Josh McGuire for the final hour of the match in oppressive heat against the Cowboys in Brisbane after his legs turned to jelly after just 20 minutes on Friday night.
Head of football Todd Greenberg said he was concerned by a number of head-injury incidents so far this season and that they are currently being investigated by the league.
"The last thing anyone wants to see is players put at risk by being sent back on the field when they should be taken out of the game, assessed and treated.Todd Greenberg
"We are determined to maintain our leadership position in this area because we have a duty to protect our players.
"The last thing anyone wants to see is players put at risk by being sent back on the field when they should be taken out of the game, assessed and treated.
"So, if we need to change our policy relating to concussion to make it stronger then that is what we will do."
Greenberg said the league would not comment any further on the head-injury incidents until it has completed its investigations.