Pretorius helped himself to three fours and four sixes as he bashed 42 runs off 20 balls to carry the Lions to 150 for three in 18.5 overs and victory with seven balls to spare.
Pacemen Sohail Tanvir and Hardus Viljoen, and spinner Aaron Phangiso had earlier claimed two wickets apiece in a stellar all-round bowling performance by the Lions that restricted the Titans to 148 for seven after being sent in to bat.
It was certainly a competitive total given the inconsistent bounce that saw several deliveries keep extremely low on an unusually poor Wanderers pitch.