Smith made a career-best 117 as South Africa clinched the three-match series with a game to spare against a Zimbabwe team, which was hopelessly outclassed.

The home side hammered 329 for six against a depleted Zimbabwe bowling attack and despite being without most of their own front-line bowlers, South Africa restricted Zimbabwe to 198 for seven.

It was the second successive time the hosts topped 300 after being sent in by Zimbabwe captain Tatenda Taibu -- they made 301 for seven when they won the first match by 165 runs in Johannesburg Friday.

Smith and Herschelle Gibbs (75) shared a fourth wicket stand of 134 off 137 balls as South Africa recovered from a shaky start.

They were 67 for three when the pair came together in the 15th over. Smith made his runs off 129 balls with five fours and four sixes, while Gibbs faced 73 balls and hit eight fours and a six.

Justin Kemp smashed a 19-ball half-century in the closing overs, finishing with 53 not out off 21 balls with two fours and five sixes.