"The unpredictable nature can count against them, but it can also be a major bonus for them. The key for us is to adapt to the conditions better than the other team," Smith said ahead of Thursday's match.

The West Indies beat South Africa in the 2003 World Cup and in the Champions Trophy in England the following year. The defeats contributed to South Africa's failure to enter the semifinals on both occasions.

But Smith denied it was a grudge match.

"I am sure it is going to be very competitive. The teams have had a mixed relationship on and off the field. Certain guys get on well with each other, but otherwise we don't know each other too well," he said.

Defending champions West Indies began their group matches on a sensational note when they defeated world champions Australia. They also beat India before losing to England in a 'dead' match.

The South African captain said his team needed to stick to their plans and keep pressure on the West Indies, who had more than one match-winner in their ranks.

"The West Indies have match-winners and, in one-dayers, one match-winner can win you a game. They have got the likes of Chris Gayle, Ramnaresh Sarwan, Brian Lara and Jerome Taylor," said Smith.

"If you can really get them under pressure and get stuck into their middle order as quickly as possible, then we will go a long way in curbing their strengths."

Smith did not believe their top-order batting was a major cause of concern, saying he was confident the batsmen would come good in the crunch match.

South Africa had played three matches on different pitches, scoring 108 against New Zealand, 219 against Sri Lanka and 213 against Pakistan.

"It is just a matter of spending some time in the middle. You have got to make a good start and take it from there. We have got guys to perform well," said Smith.

"I think most top-order batsmen have so far struggled in this tournament. I think the new ball has been a difficult phase to bat. If we can get off to a good start, it will be a huge bonus for us."

Mark Boucher, Justin Kemp and AB de Villiers are the only batsmen to have scored a half-century, while Smith, Jacques Kallis and Herschelle Gibbs are yet to fire.

"It's time all of us delivered. The pressure is there on everybody in a semifinal. Whichever top order gets off to a good start, it will allow the rest of the guys to play a far more attacking and aggressive game."

Smith said his batsmen needed to adapt themselves to the pitch here because it looked a bit inconsistent.

"This wicket looks different from the ones we have played on. It seems a bit two-paced and inconsistent. Every pitch has been different and adapting to the conditions has been the key," said Smith.

Teams
South Africa (from): Graeme Smith (captain), Loots Bosman, Mark Boucher, AB de Villiers, Boeta Dippenaar, Herschelle Gibbs, Andrew Hall, Jacques Kallis, Justin Kemp, Charl Langeveldt, Andre Nel, Makhaya Ntini, Robin Peterson, Shaun Pollock.
west Indies (from): Brian Lara (captain), Ramnaresh Sarwan, Chris Gayle, Shivnarine Chanderpaul, Runako Morton, Dwayne Bravo, Dwayne Smith, Carlton Baugh, Fidel Edwards, Corey Collymore, Ian Bradshaw, Jerome Taylor, Marlon Samuels, Wavell Hinds.