Only one Australian team can make the Super Rugby finals after the Highlanders secured their spot in the playoffs with a 34-8 win over the Jaguares in Buenos Aires.
The four-tries-to-one, bonus-point victory meant New Zealand sides have clinched all three of the wildcard spots and four of the five playoff places available to Australasian group teams.
Only the winner of the Australian conference can make it through to the playoffs, with the Brumbies and NSW Waratahs level on points heading into next weekend's final round.
The Brumbies look favourites to progress as they lead the Tahs on total wins and have an easier final-round game at home to the struggling Western Force on Saturday.
The night before, NSW play in Auckland against the Blues, who thrashed the Brumbies at Eden Park last Friday.
The Canberra-based side will be assured of finishing first in Australia even before they play, if NSW don't pick up at least a losing bonus point the night before.