Graeme Smith: down but not out © Getty Images

South Africa received an injury scare ahead of their big semi-final against Australia, with their captain Graeme Smith suffering a minor knee injury ahead of the St Lucia clash on Wednesday.

Smith hurt his knee while fielding in the match against England that enabled South Africa to qualify for the semi-final. According to a team spokesman, Smith did not play a full part in Saturday's training session.

"He has a niggle and thus didn't train as intensively," the team spokesperson told Reuters, adding that Smith was advised by team physio Shane Jabbar to manage the problem through rest.

The South African captain has scored 441 runs in the tournament so far at a strike rate of over a hundred. His five fifties include a 91 off only 65 deliveries against Scotland. Smith has also struck the second highest number of fours in this World Cup to date, second only to Australia's Matthew Hayden.

South Africa, ousted by Australia in the 1999 World Cup semi-final, are bidding to make it to their first-ever final of a World Cup. The only other time South Africa entered the last four was in 1992 when they went down to England, thanks largely to the rain rule prevalent at the time. In 1996 they lost to West Indies in the quarter-final while their 2003 home campaign ended disappointingly, with a first-round exit.