Wellington - The Bulls will meet a depleted Chiefs line-up on Friday in a repeat of last year's Super 14 rugby final. It will be the first of six ninth-round matches likely to reshape the top half of the standings.
The defending champion Bulls gave up the tournament lead after suffering their first loss of the season to the Blues last weekend.
The first-place Waratahs face a difficult task of preserving their new position when they meet the third-place Crusaders at Christchurch on Saturday.
The Stormers, who dropped from second place when they were beating in round seven by the Force, will attempt what the Bulls have never achieved: to beat the Blues in Auckland.
The fifth-place Reds will try to recover from last week's loss to the Sharks when they take on the winless Lions in Johannesburg and the Brumbies, seventh after a bye last weekend, take on the Cheetahs in Canberra.
Nearer the bottom of the standings, the 11th-place Highlanders take on the 13th-place Force on Saturday in the New Zealand tourist city of Queenstown. The Sharks and Hurricanes have weekend byes.
The sixth-place Chiefs have made only two changes to their lineup for the match at Hamilton, despite a lengthening injury list. All Blacks fullback and Chiefs captain Mils Muliaina joined that list this week, having surgery to insert a pin in his broken thumb. Muliaina will be sidelined for at least six weeks.
The Chiefs are already without All Blacks winger Sitiveni Sivivatu, with a knee injury, props Nathan White and James McGougan, lock Kevin O'Neill and hooker Aled de Malmanche. Tim Nanai-Williams will make his Super 14 debut at fullback in Muliaina's place and flanker Liam Messam will take over the captaincy.
Former All Blacks No. 8 Sione Lauaki has been cleared to play after receiving a fine rather than a suspension from the New Zealand Rugby Union as punishment for a recent assault charge. Lauaki will be sentenced on May 6 for punching a man in a Hamilton bar.
Chiefs coach Ian Foster said it was unlikely his team would use Auckland's win over the Bulls as a blueprint for Friday's match.
"We're a little bit of a different makeup," Foster said. "Our pack is in a different phase to where the Blues are at so we're going to have to come up with some slightly different ways."
Pierre Spies and Guthro Steenkamp will earn their 50th caps for the Bulls, joining eight players who have already reached that milestone in an experienced Bulls lineup.
Coach Frans Ludeke has made two changes for the match, both forced by injury. Stephan Dippenaar will replace Jaco Pretorius at center and Heini Adams will replace Derick Kuun on the bench.
Pedrie Wannenburg will play his 106th match for the Bulls, a franchise record, and will also make a record 92nd consecutive appearance.
Captain Phil Waugh and fellow Wallaby backrower Wycliff Palu have been included in an enlarged Waratahs squad for the match against the Crusaders. Chris Alcock and Locky McCaffrey, who made their Super 14 debuts against the Cheetahs last week in place of Waugh and Palu, are also included in the 24-man squad.
Waratahs coach Chris Hickey said Palu and Waugh would have to prove their fitness before being confirmed in the match 22.
"This is a big match for both teams and you want to take your experienced campaigners into big clashes such as these," Hickey said.
The Stormers have made four changes to their lineup for Saturday's match against Auckland.
J.D. Moller replaces the injured J.C. Kritzinger at prop, lock Adriaan Fondse will start for the first time this season ahead of De Kok Steenkamp, Dewaldt Duvenage will play at scrumhalf in place of Ricky Januarie and Juan De Jongh will return at center after recovering from an elbow injury.
Assistant coach Matthew Proudfoot said the Stormers could recover quickly from last week's loss to the Force.
"There's no need to panic," he said. "We don't become a poor side in a week."
Chiefs: 15. Tim Nanai-Williams, 14. Lelia Masaga, 13.
Richard Kahui, 12. Stephen Donald, 11. Dwayne Sweeney, 10. Mike Delany,
9. Brendon Leonard, 8. Sione Lauaki, 7. Tanerau Latimer, 6. Liam Messam
(captain), 5. Culum Retallick, 4. Craig Clarke, 3. Ben Afeaki, 2. Hika
Elliot, 1. Sona TaumaloloSubstitutes: 16. Vern Kamo, 17. Toby
Smith, 18. Jarrad Hoeata, 19. Colin Bourke, 20. Junior Poluleuligaga,
21. Callum Bruce, 22. Jackson Willison
Bulls: 15. Zane
Kirchner, 14. Gerhard van der Heever, 13. Stephan Dippenaar, 12. Wynand
Olivier, 11. Francois Hougaard, 10. Morné Steyn, 9. Fourie du Preez, 8.
Pierre Spies, 7. Dewald Potgieter, 6. Deon Stegmann, 5. Victor Matfield
(captain), 4. Danie Rossouw, 3. Werner Kruger, 2. Gary Botha, 1.
Substitutes: 16. Bandise Maku, 17. Bees Roux,
18. Flip van der Merwe, 19. Pedrie Wannenberg, 20. Heini Adams, 21.
Jacques-Louis Potgieter, 22. Jaco van der Westhuyzen