Wayne Bennett has dismissed talk of introducing an 18th man after three NRL clubs were slapped with heavy fines for concussion protocol breaches.
The Brisbane coach also bristled at the suggestion a player culture still existed that it was considered a badge of honour to play on after being concussed.
Newcastle coach Nathan Brown renewed calls for NRL teams to be allowed a reserve player to be injected when players are ruled out mid-game through concussion, after the Knights, Gold Coast and St George Illawarra were fined a record total of $350,000 for concussion breaches this week.
Brown was forced to leave winger Nathan Ross on the field with an ankle injury after losing two players to concussion during last weekend's loss to the Rabbitohs.
"How many players do you want on the bench?" Bennett said on Thursday
"Where does it all stop? I am not pushing for 18 players.
"We will lose a player then another and people will say 'we need 19', it's like a piece of string - there's no end to it."
Bennett also had no time for the introduction of independent doctors for concussion tests on players.
"We don't need one. These (club) doctors are ethical," Bennett said.
"You are talking about their ethics here, they have reputations.
"Any doctor in the game is on tenterhooks more than ever - they know their responsibilities."
Bennett also took aim at a claim by a Fox Sports rugby league identity, this week, that players still thought they had to play out games "or they would be bagged" after suffering a concussion.
"There was some ridiculous comment on TV the other day about the players," Bennett said.
"These guys are making statements and they have never coached a game in their life.
"They haven't been to a training session for 10 years since they retired - don't start buying into that rubbish."
Bennett believed clubs had their players' best interests at heart.
"When you get knocked out you don't know where you are but your instinct is to stay on the footy field - that's what is happening," he said.
"They are not staying on the field because someone is making them.
"We are doing everything we can to protect in their long-term help and I believe in what the game is doing."
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