The Crusaders and the Lions are embroiled in a final-round battle this weekend to claim the top rankings spot and home advantage throughout the Super Rugby play-offs.
The Crusaders, just two points ahead of the Lions, must beat defending champions Hurricanes to go into next week's top-eight play-offs as top seed and in the box seat to host the final on August 5.
Should the seven-time champions stumble in Wellington on Saturday then the Lions could leapfrog them to finish top of the final-season standings if they beat the Sharks in Durban later that day.
Eight teams have already qualified for the play-offs with the top four conference winners having home advantage in the first week of the finals against the fifth to eighth-placed wild card teams. Only the exact final places are to be decided this weekend.
All Blacks TJ Perenara, Beauden Barrett and Ardie Savea return for the Hurricanes against Crusaders, in the only changes to the team that started during last month's 31-31 draw with the touring British and Irish Lions.
The Crusaders are vying to retain their unbeaten Super Rugby record and ensure they finish top of the regular season ladder, giving them home advantage throughout the play-offs.
A win for the Hurricanes would mean a trip to Canberra to play the Brumbies in the quarter-finals, while a loss would send the defending champions off to Cape Town to face the Stormers.
The Lions face a vengeful Sharks, still rankled by their dramatic 34-29 loss at Ellis Park earlier this season.
"We have been looking forward to this game for some time, especially after what happened at Ellis Park where we felt we should have won, so we are definitely excited about this one," Sharks scrum-half Cobus Reinach said.
"In that Johannesburg game it did not work out. Hopefully we can put in a great performance and it will go our way this time."
The Sharks can avoid a long trip to play the Crusaders in the first week of the finals if they beat the Lions with a bonus point and the Highlanders are upset at home by the Reds.
Centre Juan de Jongh and loose forward Sikhumbuzo Notshe will be available for selection for the third-ranked Stormers against the Bulls at Loftus Versfeld on Saturday.
Australian conference winners the Brumbies have made 12 changes to the team that was beaten by the Reds in Brisbane last week for their final game of the regular season against the Chiefs.
Only winger Henry Speight, fly-half Wharenui Hawera and flanker Scott Fardy remain from the side that went down by a point at Suncorp Stadium, as head coach Stephen Larkham rests players ahead of their home quarter-final against either the Hurricanes or the Chiefs on July 21.
In this weekend's other games with no finals bearing, the Force may play their final game in Super Rugby against the Waratahs, the Rebels host the Jaguares and the Sunwolves take on the Blues.
The Kings and the Cheetahs, already officially dumped from the 2018 competition, play their final Super Rugby game in Port Elizabeth.