The Crusaders fell short in their bid to reach the Trans-Tasman showpiece match, which will be contested by the Blues and Highlanders.
The Highlanders moved closer to a Super Rugby Trans-Tasman play-off spot after the Hurricanes had been clinical against the Reds.
A big-name omission from Warren Gatland's original squad, Kyle Sinckler has been called up to replace the injured Andrew Porter.
The Chiefs claimed four points to remain within reach of the top two ahead of the final round of Super Rugby Trans-Tasman fixtures.
Morne Steyn sealed South Africa's win over the British and Irish Lions in 2009, and after a long absence, he is back in a Springboks squad.
The Brumbies secured only a second win for an Australian franchise in Super Rugby Trans-Tasman, stunning the Hurricanes.
The Blues and the Crusaders made it four wins from four in their Super Rugby Trans-Tasman campaigns by beating the Reds and Western Force.
The Chiefs did their best to produce a stunning comeback, but the Reds held on to secure a hard-fought victory.
Teams from New Zealand continue to dominate Super Rugby Trans-Tasman after the Hurricanes thrashed Western Force.
La Rochelle were overcome after an early dismissal, as Toulouse claimed their fifth European Champions Cup crown, a new record.