Shaun von Berg came back to haunt his former team with a maiden career five-for that dumped defending champions the Titans out of the One-Day Cup at the expense of the Knights, who won a one-sided clash by seven wickets in Centurion on Sunday.
The leg-spinner, a SuperSport Park favourite for most of his career, claimed List A best figures of five for 33 to help dismiss the home side for a paltry 138, before Jacques Snyman's powerful 35 led the visitors to the target in just 30.1 overs for a bonus-point win.
They got there with a few late bumps, although that mattered little as victory was the most important factor for both teams heading into what was effectively a quarter-final.
The match also concluded the regular season of the competition, with the Central Franchise pipping their more illustrious hosts to the final qualifying position.
They ended in fourth spot and will now travel to Durban to face the Dolphins in Tuesday's first semi-final, with the second last-four showdown to be hosted by the Lions against the Warriors on Wednesday.
It has been a remarkable turnaround for the Knights, who after four matches of the 2019/20 campaign were without a win.
They won the toss and opted to bowl in Tshwane, with their bowlers doing the business in style.
Match top-scorer Tony de Zorzi (61 off 79 balls, 7 fours) did hand the hosts a good start as they reached 58 for one in the 14th over.
But things went horribly wrong from there, with Von Berg running riot as he beat his previous best figures of four for 17.
Both the spinner and Mbulelo Budaza (3/26), who provided fine support along with Marco Jansen (2/30), moved to the top of the competition wicket-takers' column with 18 wickets each - the Titans shot out in 31.5 overs.
The Knights raced out of the blocks in reply, with Snyman and Andies Gous (25) adding 59 for the opening wicket, before Keegan Petersen (20) helped them reach 102 for two.
A cluster of wickets then fell - two each to Khwezi Gumede (2/24), Matthew Arnold (2/43) and Dayyan Galiem (2/37) - but Grant Mokoena (18 not out) helped them get over the line.
- Cricket South Africa