The South African teams maintained a perfect record at home as Warriors reached the 154-run target with seven wickets in hand and ten balls to spare against Wayamba XI in their league match of the Champions League.
Mark Boucher scored 40 and JP Kreusch hit a quickfire 37 as they shared a crucial fourth-wicket partnership.
Earlier,South Africna paceman Juan Theron took three for 23,including two wickets in the first over of the match,to help restrict the Sri Lankan champion team.
Brief scores: Wayamba Elevens 153 for 9 in 20 overs (Jeewantha Kulatunga 59,Kushal Perera 39; Juan Theron 3/23,Makhaya Ntini 2/34,Johan Botha 1/21); Warriors 156 for 3 in 18.2 overs (Mark Boucher 40 n.o,JP Kreusch 37 n.o)