Samoa are under no illusions about their task against defending World Cup champions South Africa on Friday - a game which will decide if Samoa remains in the tournament.

Nothing less than a win will do for the Pacific Island nation, who need to beat the Springboks or at least claim a bonus point and then hope that Fiji beat Wales without the Welsh securing a bonus point.

It is a long shot in both ways but captain Mahonri Schwalger said it was all in Samoa's hands.

"I think it is all about attitude. In this World Cup, there are a lot of tight tests in these games. The team that turns up with the right attitude will probably come up on top," he said.

Schwalger said he was not so much worried about South Africa but more concerned about how his own side would perform.

"We know it is a hard game. We have to make sure these guys are cranked up for Friday," he said.

"You can't go in half-hearted. You can't have the attitude that you are going to come second. I have said before it is all about attitude and it is something we need to work on."

Motivation should not be an issue for Samoa, he added, with the challenge of playing one of the best teams in the world motivation enough.

"You have to make sure you are on the top of your game if you want to compete against these guys. South Africa is the world champ and that is in the back of my mind already, that it won't be an easy game," Schwalger said.

"These are the games you want to play rugby for. You do not take these opportunities lightly."

Lack of familiarity with South African rugby might have been an issue in the past, but it did not apply this time around.

"Some of our players play these guys three, four times a year. So you get some knowledge to share around," he said.