The Russian-based hard man is in line to make his first appearance of the tournament in the hosts' last Group A match against France in Bloemfontein on Tuesday - a game where the hosts nation cling to the hopes of a mathematical miracle but in reality already look a beaten bunch.
"We could have been a lot more determined. We can't expect at this tournament to just play your style. In some games you have to sacrifice and be able to do more of a dirty job," he told a news conference in Johannesburg.
Sibaya, who has a reputation for straight talking, played all three matches at South Africa's last World Cup appearance in 2002 but has been benched for this tournament.
The suspension of Kagisho Dikgacoi opens up a berth for him but coach Carlos Alberto Parreira must chose between him and the up and coming Thanduyise Khuboni.
"I believe that the game against France will be very difficult and we have to show more character. We need more fighting spirit," added Sibaya.
A win against France would still give South African an outside chance of making it to the knockout stage, but it would also depend on the result of the other Group A game between Mexico and Uruguay, which will be played at the same time.
"Maybe a miracle will happen but it is a bit like climbing Mount Everest," admitted Sibaya.
Any realistic chance the hosts might have had vanished on Thursday night with Mexico's 2-0 win over France in Polokwane. Mexico and Uruguay both have four points and the French and the South Africa a single point from their first two matches.
"There were a lot of mixed emotions after the Mexico win. It's not easy now to encourage each other. We need five or six goals to turn it all around," he said in a resigned tone.
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