In Super Rugby terms, Allister Coetzee leads Jake White 1-0, so Whites Sharks will be keen to level the scores at Kings Park. Photo: Steven Haag and Ashley Vlotman

Sydney - The NSW Waratahs may have locked up top spot and a home semi-final but four games in this weekend's final round all have a bearing on the make-up of the Super Rugby play-offs.

The Waratahs are seven points clear and won't lose their top billing even if they lose their Australian derby against the Queensland Reds in Brisbane on Saturday.

But there is a mighty tussle going on below the Tahs to decide who plays who in the following week's Super 15 qualifiers.

The two top finishing teams will skip the qualifiers and host semi-finals on July 25-26, but the third-placed team will have to go through the qualifiers, although they will have home advantage.

Seven-time Super Rugby champions Canterbury Crusaders shade South African conference winners the Sharks on points differential for second spot heading into Saturday's home match with the fourth-placed Otago Highlanders.

The Highlanders could finish New Zealand conference winners if they beat the Crusaders with a bonus point, but they have lost their last four encounters with Canterbury.

Crusaders coach Todd Blackadder has made one change with lock Sam Whitelock returning to the starting line-up.

“The Highlanders are a gutsy side and we know that they will be putting everything they've got into this encounter,” Blackadder said.

“We are going to have to put in the performance of the season to come out on top, and that is exactly what the team has committed to doing.”

The pressure is on Jake White's Sharks in their testing away game with the improving Stormers in Cape Town on Saturday.

The Sharks can still finish second if they win, but the Stormers have won three of their last four home meetings with the Durban-based side and are unbeaten in their last four outings.

“It doesn't matter what happens in the other games, we must just get a win on the weekend,” White said.

“We want to win again. We haven't won in a while.”

The Sharks, who have tasted defeat in four Super Rugby finals, have been shaky, losing their last two games.

Twice winners ACT Brumbies and Western Force get the chance to clinch a play-off berth with a win in their Australian derby in Canberra on Friday.

Both teams are level on 40 points and it will be winner takes all in the national capital.

The Brumbies have proved vulnerable in final round matches and haven't won in the last round of Super Rugby since 2007.

The most famous of those losses was their 2012 choke against the Auckland Blues, not only relinquishing their 13-week run at the top of the Australian conference, but missing out on a finals spot altogether in the process.

Last year the Brumbies suffered a shock loss against the Force in Perth whih cost them an all-important top-two finish.

Coach Stephen Larkham has shrugged that off and said: “We are a big game team. And this is certainly a big game.

“We've had a couple of finals campaigns. We had a qualifying final here at home last year against the Cheetahs, then we went over (to South Africa) and beat the Bulls.”

If Force win on Friday they will be in their first Super Rugby finals' campaign.

Defending back-to-back champions Waikato Chiefs can still make the finals after a disappointing season but must knock over the Blues in Auckland on Friday.

Their win last week over the Wellington Hurricanes was the Chiefs' first in four outings, but the Waikato team have won on their last three trips to Eden Park and should they win again they will knock the Hurricanes out of the play-offs.

The Hurricanes, currently in fifth spot, are just one point ahead of the Chiefs but have a bye this weekend.

In the remaining games with no play-off bearing, the Northern Bulls host the Melbourne Rebels in Pretoria and the Golden Lions face the Central Cheetahs in Johannesburg. – Sapa-AFP