Bulls, Chiefs in box seat for Super play-offs
Victories in South African and New Zealand derby clashes would seal the top two spots
Agence France-Presse in Sydney
Triple champions Northern Bulls and holders Waikato Chiefs can lock up the top two spots - and with them, semi-final hosting rights - in this weekend's final Super 15 regular round of matches.
The Bulls will take a big step towards hosting this season's Super Rugby final if they can win their South African derby against the Western Stormers in Cape Town to finish top after 20 rounds of the southern hemisphere provincial series.
The Pretoria-based Bulls are two points clear of the Chiefs, who face a tricky New Zealand derby with the Blues in Auckland if they are to maintain their top two spot.
Only Australia's ACT Brumbies, former two-time winners and, mathematically, seven-time champions the Canterbury Crusaders, can knock the Chiefs out of the top two places.
The Brumbies, resuming after a month's break for Australia's home test series against the British & Irish Lions, take on Western Force in Perth tomorrow, where they have lost only once in four trips, while the Crusaders host the Wellington Hurricanes.
The Bulls, who have lost on two of their last three trips to Cape Town, have Francois Venter in for injured midfielder Jan Serfontein, and Jano Vermaak taking over from injured scrum-half Francois Hougaard.
The suspension of Wilhelm Steenkamp opened the door for 19-year-old Jacques du Plessis, who was included as replacement lock.
Captain Dewald Potgieter said the Bulls would have to step up their approach and execution.
"We did not react well in certain situations when placed under pressure last weekend and will have to improve on that," Potgieter said. "The Stormers have momentum and the home crowd on their side, and this being the big North/South derby, we will have to front up. This will be our biggest test this season."
Springbok captain Jean de Villiers has recovered from his sternum injury and will lead the Stormers.
The Chiefs have made several changes, with prop Toby Smith starting and Liam Messam back after a back injury. Robbie Robinson and Lelia Masaga are on the wings and Tim Nanai-Williams (centre) and Andrew Horrell (fullback) have been named.
"We are obviously pretty disappointed with our performance last week but we are excited about the opportunity to redeem ourselves," coach Dave Rennie said. "We know the Blues will want to put in a big performance in their final game of the season."
Wallaby flanker George Smith will be on the bench, with Colby Faingaa starting in the number seven jersey for the Brumbies, who have been boosted by the return of seven Wallabies from national duty.