The fixture, which has been moved to a neutral venue at Stade Ahmadou Ahidjo in Yaounde, Cameroon, would be an vital part of Bafana's quest to qualify for the 2014 World Cup in Brazil, he said.
"In our minds, there is nothing on offer other than victory. This is a very important match for us if we want to realise our dreams of going to the World Cup in Brazil.
"The good thing is that it is in our hands, and we have to make it happen."
Nunes was not part of the Bafana squad which beat CAR 2-0 in Cape Town in March, but said his team had the quality to get the result it wanted.
"I saw the highlights of the match [in Cape Town]. We created a lot of chances and should have won by a bigger margin.
"They also showed some glimpse of brilliance, so we have to be very cautious in our approach, but with the quality of the players in the squad I am very confident that we can get a positive result on Saturday.
"It will be very hard but we have to believe in ourselves."
Bafana Bafana had two cancelled flights on their way to their Yaounde base, and missing a day’s training session.
The Slovakia-based Nunes was recalled to the squad in May, and played a major role in the 2-0 win over Lesotho. He fills the gap left by the injured Tsepo Masilela.
Nunes said he was happy to be back in the national set-up.
"It was good to return to the national team after such a long time. The Lesotho game was a good match and a very good feeling for me," he said.
Bafana were due to have their final training session at the match venue on Friday afternoon.