The Lions leapfrogged the Crusaders to finish top of the overall Super Rugby standings thanks to a 27-10 victory at the Sharks in the final round of regular-season fixtures on Saturday.
Defeat for the Crusaders at the Hurricanes earlier in the day had left the Sharks in a peculiar quandary - win and face a trip to Christchurch in the play-offs, or lose and head to Johannesburg for another clash with the Lions.
With that in mind, defeat was perhaps preferable for the Sharks on this occasion, while victory for the Lions sees them avoid a meeting with the Highlanders in the quarter-finals.
Garth April gave the Sharks an early lead but the Lions went into half-time with a 13-10 advantage thanks to tries from Malcolm Marx and Andries Coetzee, before Jaco Kriel crossed in the second period as the visitors racked up 14 unanswered points.
It should be noted that, on their way to the top of the overall standings, the Lions have not played any fixtures against New Zealand opposition during the regular season.
In the day's other all-South African clash, the Stormers won an 11-try thriller against the Bulls 41-33.
The Stormers will host the Chiefs in the quarter-finals but will need to shore up their defence after an open encounter in which the teams scored three first-half tries apiece.
The visitors pulled clear at the beginning of the second half at Loftus Versfeld through touchdowns from Siya Kolisi and Damian Willemse, but Piet van Zyl and Jesse Kriel made the Stormers sweat by reducing the gap to 34-33 with 10 minutes to go.
It was not until the 77th minute that Seabelo Senatia finally put the result beyond doubt, getting on the end of a Dillyn Lleyds chip to cross for the decisive score.
Super Rugby Quarter-Finals
Lions v Sharks
Crusaders v Highlanders
Stormers v Chiefs
Brumbies v Hurricanes