Michael Cheika believes video replays have become king in rugby, meaning players and coaches must adjust their games accordingly to avoid citings and suspension.

The Wallabies coach has already seen Michael Hooper suspended for one week at the Rugby World Cup following an armless cleanout on England's Mike Brown, while  David  Pocock earlier this week warned over an alleged knee on Wales hooker Scott Baldwin.

Cheika will have a fully-fit squad, providing Pocock and Israel Folau recover from niggling injuries, for the Wallabies' quarter-final clash with Scotland at the weekend, but the same can't be said for the underdogs who have lost forwards Jonny Gray and Ross Ford to three-week bans.

"First of all, I haven't seen the incident that the lads got suspended for," Cheika said. "But, I'm being genuine here, I feel for them because [it's a] World Cup, you've worked hard for it and then, when you get to the finals, possibly two or three finals, that they miss out. But the same happened to Michael Hooper last week.

Michael Cheika speaks to the media© Dan Mullan/Getty Images

"It's the small things. Hooper's grandparents came over to watch him play and he was suspended and they had to move on and go to the next thing. I know they're little things but they are very important."

It's been a big few days at the citing office with Ireland's Sean O'Brien suspended for one week for striking Pascal Pape, in an incident that France coach Philippe Saint-Andre described as "assault".

O'Brien's minor punishment has caused uproar on social media after veteran Samoa Alesana Tuilagi received a five-week ban for leading with the knees earlier in the tournament.

The difference in sanction lengths and, in some cases, whether an incident is cited altogether, has raised questions over the consistency of the system; there is also the issue as to whether a yellow card serves as an appropriate sanction while a similar unseen incident, later picked up by the citing commissioner, can see a player miss an entire match or more.

Cheika has no problems with the consistency around the citing and punishment process, but has instead putting the onus on the game's players and coaches to move with the times.

"I'm not concerned about that [consistency]," he said. "I think that the video now usually tells the story and it's just the way it is.

"You get a decision that goes for you and a decision that goes against you. Now I wouldn't have been like that maybe four or five years ago - I was probably a bit more fiery about it all.

"But you've got to accept the way it is and, if you have the choice, you can either accept the way it is and then play under those [rules] or not be involved in it."

While many rugby fans have been a little confused as to why some incidents of foul play have gone unpunished at the World Cup and others have been dealt with severely, Cheika said World Rugby had made it clear in the lead-up to the tournament exactly what the referees would be looking out for.

"They were very clear, the referees and the authorities have been clear about what's the focus points for them way out, not just at the tournament," he said.

"Like they sent us out all the things that they're going to be focusing on around foul play, the neck rolls, the tip tackles ... so everyone knows it. And I don't think the tip tackles are often intentional, it's just the way it happens."