Willie Mason, Ben Matulino and Jayson Bukuya face an anxious wait to learn how the match review committee interprets the NRL’s hastily-introduced, new crackdown on the shoulder charge.

All three produced no-arms tackles at the weekend that are sure to come under scrutiny, even though none of them drew penalties from the referees.

The rest of the competition will also be watching closely for Monday’s decisions.

Friday’s NRL announcement that any shoulder charge “with force” would now draw a charge was intended to improve player safety and remove ambiguity, but it left questions unanswered – including what level of contact constitutes “force”.

“They’ve written these new interpretations and what they entail, I’m not sure,” admitted former Dragons star turned Fox Sports commentator Mark Gasnier.

Veteran Manly forward Mason appeared to tuck his arm in and drive his shoulder into the chest of South Sydney’s Tom Burgess during the Sea Eagles’ 28-8 win at Brookvale Oval.

Despite Rabbitohs captain Greg Inglis’ appeal for a penalty, play went on and when the referees found a knock-on in the play the ball, Mason received back pats from teammates.

Warriors enforcer Matulino pulled off a monster hit on St George Illawarra playmaker Gareth Widdop in his side’s heavy loss in Wellington, and he did not wrap his arms around the attacker.

Not only did Sharks forward Bukuya’s apparent shoulder charge on North Queensland fullback Michael Morgan go unpunished by the whistleblowers, it turned the tide at a key moment.

With his side leading 24-18 with three minutes on the clock at Remondis Stadium, Bukuya forced Morgan into the in-goal and Wade Graham scored soon after to ice the game.

The latest crackdown came amid controversy four days after Sydney Roosters prop Kane Evans escaped MRC punishment for a massive hit which decked Canterbury’s Sam Kasiano.

Prior to the rule change, a shoulder charge did not earn a MRC charge if there was “no forceful movement of the head or neck” of the tackled player.