The hosts were in strife, setting a target, but rallied to post a competitive 185/6 that proved too many for MI Cape Town to chase under the lights on a balmy highveld evening.
In the chase, Rassie van der Dussen (15) launched Lungi Ngidi for a beautiful six over long off, but ultimately Ngidi got his man the following over. Ryan Rickelton then skied a wide length ball to backward point and was livered with himself for his shot selection.
Nicholas Pooran hit some lusty blows (17), but then he perished in a soft dismissal and left the field furious.
MI Cape Town's chase then suffered a massive blow. Corbin Bosch and Karim Janat both fell cheaply to Gideon Peters in his double-wicket maiden, then Keshav Maharaj got in on the action as George Linde was caught on the fence and they were teetering at 55/6 in the tenth over.
Reeza Hendricks and Jason Smith steadied the ship with a 24-run partnership, but the pressure was too great and Hendricks was left alone on 68 (50) as MI Cape Town fell 53 runs short.
Earlier, MI Cape Town put the hosts in to bat. Spinner George Linde managed to tempt Shai Hope, who holed out Nicholas Pooran in the covers. Conor Esterhuizen looked great for his 24 before Proteas paceman Kagiso Rabada castled him in the fifth over.
Wihan Lubbe and Jordan Cox were solid, albeit pedestrian in scoring. The introduction of captain Rishad Khan worked for MI Cape Town as the dangerous Lubbe spooned one to short third man, leaving them 69/3 at the halfway stage.
Rabada struck again with a superlative yorker that shattered Cox's stumps, leaving them 89/4. That left Dewald Brevis and Sherfane Rutherford at the crease with the hosts needing to put their foot down. And that they did.
They bludgeoned six sixes a they put on 69 from 34 to put some respect on the innings. They benefited from back-to-back dropped chances, both of which went incredibly high into the Pretoria sky and were shelved as a result.
Brevis would get caught behind off Karam Janat for 34 off 19, but Rutherford continued in belligerent fashion. The West Indian would be caught in the final ball of the innings, but he'd scored 53 (27) important runs.
Donovan Ferreira has been named as captain of Joburg Kings for the remainder of the SA20, replacing Faf du Du Plessis who has been ruled out after sustaining a right thumb ligament tear.
Durban's Super Giants kept their SA20 campaign alive with a tense two-wicket victory over table-topping Sunrisers Eastern Cape at St George's Park, surviving a chaotic finish to claim only their second win of the season.
The Pretoria Capitals and MI Cape Town were the day's winners as the SA20 competition enjoyed a rare interruption-free Saturday following a run of rain-affected matches earlier in the week.
The SA20 clash between Durban's Super Giants and the Sunrisers Eastern Cape was abandoned on Friday night due to rain.
