South Africa captain Graeme Smith has admitted that it has been an "emotional" ride as he prepares to skipper his 100th Test match on Friday.

Smith will lead out his side in Johannesburg to become the first man to captain his country in 100 Tests and the opening batsman, who is also celebrating his 32nd birthday, has revealed that it will be one of his "proudest moments".

Speaking on a television special to mark the feat, Smith said: "It has been emotional and humbling.

"When I wake up tomorrow, turning 32 and leading South Africa out is going to be one of the proudest moments in my career and my life."

Smith has been the captain of the Proteas since 2002 when he replaced Shaun Pollock to become South Africa's youngest ever skipper at the age of 22.