With one round left in the regular season, the Highlanders sit in sixth position and can not now be caught by a team outside the top eight.
The Sharks lost 27-16 to the Stormers over the weekend, which leaves the South African side, which is ninth on 32 points, eight points behind the Highlanders.
The Highlanders are on 40 points, while the Jaguares are two points behind in seventh place on 38 and the Rebels are eighth on 35 points.
The southern franchise has no chance now of reaching the top four and hosting a quarterfinal after its disappointing 45-22 loss to the Crusaders in Christchurch on Friday night.
The Hurricanes all but cemented fourth place after a 42-24 win over the Blues in Wellington on Saturday night.
The chance of getting into fifth spot and taking on the Hurricanes in the first week of the playoff looks remote for the Highlanders.
It would need to win big over the Rebels this Saturday night at Forsyth Barr Stadium and hope the Chiefs are completely crushed by the Hurricanes in Hamilton on Friday night.
Both the Highlanders and Chiefs would then be tied on 45 points, with 10 wins each. It would then come down to points differential, which is not pretty for the Highlanders.
The Chiefs have a positive differential at the moment of 91 points, while the Highlanders have a negative 14 points.
The Rebels will have plenty to play for, as the equation is simple for them — win and they are in.
Lose and the Melbourne-based side will have a nervous night hoping the Jaguares beat the Sharks.
The Jaguares have qualified for the playoffs for the first time, although their seven-match winning run came to an end, losing to the Bulls yesterday, going down 43-34 in Pretoria.
As it stands at the moment, the Highlanders, in sixth, would take on the third-placed side, which is the Lions of South Africa.
The Lions had a bye over the weekend and watched as the Waratahs thumped the Sunwolves 77-25, sending the New South Welshmen to second on the table.
The Waratahs will take on the Brumbies in Sydney this Saturday night, while the Lions host the Bulls.
The Crusaders have already nailed down the top spot and face the Blues this weekend.
Should the Rebels win with a bonus point, and the Jaguares also win, and the Highlanders lose with no bonus point, the Highlanders will slide to eighth and have to take on the Crusaders in Christchurch.
The Highlanders could head to South America.
The Jaguares may get up to take the leadership of the South African conference and host a playoff game. The Argentinians need to beat the Sharks and then hope the Lions dip out against the Bulls.
There are plenty of scenarios and what-ifs, but the Highlanders just have to keep it simple and win on Saturday night against the Rebels.
The real worry for the side is its leaky defence, which has now conceded 408 points, 90 of them in the past two matches.