'Six-week ban if he was playing rugby union'

Marika Koroibete somehow managed to avoid suspension after putting Dallin Watene-Zelezniak in hospital with a 'sickening' shoulder charge.

The Storm winger pulled off the try-saving hit in Melbourne's clash against Penrith on Saturday night, but inexplicably escaped a penalty.

Watene-Zelezniak was forced to undergo scans after being clobbered by what was deemed nothing more than a "bump" by the NRL.

Panthers coach Anthony Griffin said Watene-Zelezniak was in doubt for Sunday's clash against Manly, professing he's "confused as to what is a shoulder charge and what isn't a shoulder charge".

Senior SANZAR officials have confirmed Koroibete would probably be rubbed out for up to six weeks if he produced a similar hit in rugby.

The Fijian flyer is poised to switch to the 15-man code in 2017 after signing on with the Melbourne Rebels, but he may need to change his tackling technique quick smart.

NRL match review committee co-ordinator Michael Buettner says Koroibete's effort was "a desperate tackle, or a bump".

"Whilst there was no wrapping of the right arm by the defender, you can see clear separation between the upper arm and the body," Buettner said.

"Koroibete was heading in the same general direction as Watene-Zelezniak, who was approaching the try line with both players at great speed. That's clearly different to a front-on challenge where the arm is tucked into the side of the defender with no attempt to make a conventional tackle."

SANZAR says Koroibete's hit would have likely have resulted in a penalty try and yellow-card in rugby union.

Koroibete's let-off wasn't the only contentious non-charge from Round 13, with South Sydney prop Nathan Brown also avoiding suspension despite appearing to stomp on an opponent's groin.