Sydney – Injury-hit leaders the Sharks will be without key players and opponents NSW Waratahs are missing Wallaby ace Israel Folau in this weekend's feature Super 15 match.
The Durban-based Sharks, leading the competition by two points from Australia's ACT Brumbies, have been dealt a blow with the loss for the season of lock Pieter-Steph du Toit, while fly-half Patrick Lambie (bicep) and scrum-half Cobus Reinach (fractured hand) are out for six weeks.
The Waratahs are fifth overall and have a good record in Durban, winning two of their last four games there, but they are without their eight-try fullback Folau, who has a bruised throat, for Saturday's match.
The Northern Bulls will try to make it two defeats in a row for back-to-back champions Waikato Chiefs in Pretoria on Saturday.
Australian conference leaders the Brumbies have a derby against the Rebels in Melbourne and the Queensland Reds will look to bounce back from their unproductive trip to South Africa against the Western Stormers in Brisbane.
In Durban, the Sharks' depth will be tested against the Waratahs as they look to bounce back from their first defeat of the season, 23-19 to the Bulls in Pretoria last weekend.
The Waratahs view Saturday's match as an opportunity to prove they're no one-man band with Folau missing.
Folau has made a sensational start to this season's Super Rugby with eight tries in four games.
“It's pretty obvious that Izzy adds a lot to our group in terms of his attacking ability and overall game,” Waratahs captain Dave Dennis said.
“But we've still got great depth and it creates an opportunity for someone else. We're not too worried about having someone else stepping up.”
Bulls coach Frans Ludeke has made one change for the game against the Chiefs with winger Akona Ndungane, who missed last week's win over the Sharks because of compassionate leave, back in place of Sampie Mastriet.
Skipper Victor Matfield said the Chiefs will be a stern test.
“They are well balanced with a lot of strike power at the back, but also have a solid and strong first phase in their play,” Matfield said.
“We will have to be very accurate and use our changes if we want to win,” he said.
The Chiefs had plenty to ponder on the journey to Johannesburg after they were upset 18-15 by the Western Force in Perth last weekend.
The Chiefs' performance was littered with unforced errors, handling lapses and a high turnover rate, while their lineout also had its anxious moments.
Waikato have not won at Loftus Versfeld since 2001 and have lost in their last six visits, so this will be a tough place to bounce back.
Wallabies centre Christian Lealiifano will make his Super Rugby return from the Brumbies' bench, while his centre partner Tevita Kuridrani is back in the starting lineup for the Rebels on Friday.
Lealiifano has spent the last five months in rehabilitation after ankle surgery, while Kuridrani missed last week's win over the Stormers to attend a funeral in Fiji.
The Rebels have dumped former Wallaby scrum-half Luke Burgess to the bench among six changes with Nic Stirzaker coming in at number nine as coach Tony McGahan seeks fresh attacking impetus for his struggling side against the Australian conference leaders.
The Queensland Reds will be without their Wallaby flanker Liam Gill (hamstring) and fullback Aidan Toua (pectoral) for the home encounter with the Cape Town-based Sharks, who have made seven changes after their third Australasian tour defeat last week.
In the weekend's remaining games, Canterbury Crusaders have home advanatage against the Wellington Hurricanes and in another New Zealand derby, the Blues host the Otago Highlanders in Auckland.
The Central Cheetahs, Golden Lions and Western Force have byes. – Sapa-AFP