The Lions secured their place in Saturday’s playoff match after beating the Cobras by seven wickets at Kingsmead on Friday.
The men from Cape Town needed a bonus point victory to have any sort of chance of making it past the group stage.
But, another determined performance by Temba Bavuma’s charges meant the Lions kept their hopes alive of facing the Dolphins in Sunday’s final.
Batting first, the Cobras struggled to get their innings going, losing captain Tony de Zorzi off the very first delivery.
Kyle Verreynne made 21 but fell to Lutho Sipamla before Zubayr Hamza had to retire hurt from suffering a groin problem.
The Lions bowlers continued to apply the pressure, picking up the further wickets of Jason Smith (2) and George Linde (22).
Christiaan Jonker provided a little cameo of 45 from 38 deliveries but he was dismissed by Malusi Siboto as the Cobras managed to post 144-6 in their 20 overs.
Reeza Hendricks immediately took the attack to the Cobras bowlers and provided the Lions with a good start, despite losing Ryan Rickelton for nine.
Hendricks and Bavuma ticked away at the target with the former bringing up his half-century in the process. Bavuma was eventually caught for 29, bringing an end to the 84-run partnership.
Ziyaad Abrahams then accounted for the big wicket of Hendricks, who was caught behind by Verreynne for 75.
Wiaan Mulder and Rassie van der Dussen sealed the victory for the Lions by getting over the line in the final over.
The men from Johannesburg will face either the Titans or the Warriors in the playoff on Saturday. The Titans, though, need to beat the Dolphins on Friday afternoon to book their spot.