NRL referees have been told to watch for any attempts by defenders to keep playmakers out of sixth-tackle plays after claims Brisbane forward Adam Blair held Cowboy Johnathan Thurston down last week.
The Kiwi international appeared to pin Thurston down long enough to keep him from taking part in his team's final tackle play at a crucial stage in the second half of last Saturday night's 16-12 loss to the Cowboys.
While Blair would like to take credit for the tactic, which has been widely discussed as being a professional foul, sources say he was merely trying to prevent Thurston from retaliating to his tackle which he appeared to resent.
With some concerns the tactic may be used again on Thurston and other playmakers, referees have been told to act if they deem it to be a professional foul.
Meanwhile Bulldogs forward Greg Eastwood has been sent a letter of concern over a tackle which injured St George Illawarra halfback Benji Marshall last weekend, when the Bulldogs snuck through their elimination final 11-10 on a Josh Reynolds golden point field goal.
Eastwood put his leg in between Marshall's legs to help affect a tackle, which under the rules is not allowed.
A player can use an outstretched leg to bring an opponent down, as long as he uses his hands on the player in the process.
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