Hasler's Eagle-eye spots refs' extra scrutiny on offside rule

NRL referees have been urged to ping 10-metre offside penalties in a bid to maintain the integrity of the six-again rule, which caught Des Hasler's attention as he settled in to watch Thursday night footy.

Hasler raised the prospect in his weekly media conference after Thursday's Rabbitohs-Dragons clash in which six offside penalties were called by referee Ashley Klein.

Four of those were awarded within the first half an hour as Klein set the standard.

NRL.com has been told no official crackdown on the 10 metres has been ordered by head office or communicated to clubs.

But referees' boss Bernard Sutton is understood to have made it a key focus of his coaching in recent weeks.

NRL whistleblowers have also been encouraged to adopt a more open interpretation of knock-on calls, with a ball hitting the deck not necessarily an automatic knock-on.

"I saw last night they've started penalising the 10 metres," Hasler said on Friday.

"Are we back to where we started, I'm not sure?

"It was pretty clear from what you hear that Ashley Klein was really set about making a point of the 10 metres last night.

"It was probably a warning shot across the bow - it is something we have to be mindful of.

"There's a correlation between being close enough to call six-again but too close to stand offside and not wanting to blow penalties, because we don't want time out of the game, we want the fatigue element."

Hasler confirmed Dylan Walker was set to take his place against the Panthers provided his ankle injury does not flare up again on Saturday morning.

Back-rower Joel Thompson is also firming to play after rehabbing his ankle concern around the clock this week to take his place in Indigenous Round.

Hasler praised Cade Cust's development at five-eighth in Walker's absence, with the 21-year-old close to finalising a two-year extension.

"We are not rushing anybody," Hasler said.

"It is great to see a young fella like Cade step up. It's great for our depth.

"[But] he [Walker] brings that level of experience and big match mentality - he is looking forward to playing."

Panthers counterpart Ivan Cleary was less forthcoming on Api Koroisau (elbow) returning against his former club after being named on Penrith's extended bench, stressing the livewire No.9 would not be risked if he was in any way short of fitness.