An exasperated Victor Matfield has slammed the "stupid things" which the indisciplined Springboks have done to put their Tri-Nations title hopes on the slide.

"The discipline is there. It's just that we are doing stupid things out of character at the moment which we have to cut out.

"You can play hard rugby within the laws and that is how we want to play it. We don't want to get yellow cards. Our discipline has actually been good. I think in the first game we only conceded five or six penalties, and only nine in the second game against the All Blacks.

"Discipline is very important but it's also very important to adapt to the referee and the way he interprets the laws on the day. That is something we need to adapt to as quickly as possible during a game. If we get a feel for what the referee wants in the first 20 minutes, how he is at the scrums and the breakdown, then after that you have to adapt and play accordingly.

"We all know that once New Zealand get momentum in their game it is very difficult to stop them. That's how you beat them, by putting them under pressure from the first minute.

"But in the two games against the All Blacks, we got yellow cards early on and that gave them a lot of momentum and made it tough for us especially with them playing at home. It is a lesson we have to learn for this Saturday against the Australians."

But it isn't just in the field of discipline that South Africa must improve against the Wallabies, warned Matfield. "We need to do everything better" he admitted.

"We are not right up there at the moment and the two areas we have definitely had a good look at this week have been the breakdown and our defence. Hopefully, they will both be better on Saturday."

Matfield insisted that notions of referees ganging up on the Boks had to be got out of the players' heads. "We have to adapt to this referee. Both teams play under the same laws so it's the team that adapts quickest that will get the benefits."

The Springboks know that this weekend will define their Tri-Nations campaign.