Harare, July 20 -- South Africa produced a commanding performance to defeat Zimbabwe by seven wickets in the fourth match of the Zimbabwe T20I Tri-Series here at Harare Sports Club today. Chasing a modest target of 145, the Proteas reached the finish line in 17.2 overs, powered by captain Rassie van der Dussen's unbeaten 52 off just 41 balls. He was well supported by Rubin Hermann, who smashed 63 off 36 balls deliveries, and Dewald Brevis, who added a brisk 13*. Earlier, South Africa won the toss and opted to bowl first. Zimbabwe managed to put up 144/6 in their 20 overs, with Brian Bennet top-scoring with 61. Ryan Burl scored 36* in 31 balls, but found little support from the rest of the lineup. Corbin Bosch (2/16) and Nandre Burger (1/20)...