The NRL won't guarantee Ashley Klein will remain as the game's premier referee and take charge of this year's grand final, after two blunders brought the veteran whistleblower's performance under the microscope.
Klein found his name in the headlines for all the wrong reasons after Melbourne edged past the Sydney Roosters in a 18-13 win in Friday night's semi-final.
Klein failed to blow for a knock-on from Melbourne hooker Harry Grant when the Roosters were on the attack, with the Storm soon going up the other end and scoring a try through Marion Seve.
The referee later opted against penalising Sam Walker for glancing Grant in the head while trying to execute a tackle in the dying stages of the match.
Those two errors meant NRL head of football Graham Annesley refused to confirm whether Klein, who refereed the 2022 grand final and the past two State of Origin series, would take charge of a preliminary final this weekend.
"That decision hasn't been made yet" Annesley said.
"We've spent this morning reviewing both games.
"We'll review all the information on match officials throughout the year and across the weekend.
"We look at the statistics around all their matches, in terms of enforcement of certain parts of the game.
"We will then make a decision we think is appropriate, given the significance of the games and making sure that we've got referees on the field that are the best available officials to perform in those matches."
Referring appointments for the two preliminary finals will be made on Tuesday.
Annesley said Klein had offered apologies for the uncharacteristic blunders and said he believed Grant should have been awarded a penalty late in the game when he was collared by Walker.
Grant laid down on the ground demanding the bunker review the hit, but Klein told him to get up and play the ball.
After a rule change last year, the bunker can only intervene and tell a referee to blow for a penalty if the incident was deemed a reportable offence.
"It was almost becoming farcical with players staying down, (last year)" Annesley said.
"When they (the bunker) reviewed this decision, they couldn't say to the referee that it was a high hit and it should have been penalised because it would have been contrary to what we've done all season."