BULLS' No 8, Pierre Spies, was yesterday declared unfit by the team doctor and will miss Saturday's Vodacom Super 14 game against the Waratahs at Loftus.
Spies limped off the pitch with a knee injury during Saturday's match against the Brumbies in Pretoria, which was initially postponed from Monday until today to give him time to recover.
Coach Frans Ludeke confirmed yesterday that Spies would not play on Saturday. He will be replaced by Danie Rossouw, who missed the Brumbies match due to a neck strain.
"We have lost one of our main ball carriers in the highly rated Spies and his absence will really be felt.
"But luckily we have someone who can rise to the occasion in the likes of Danie. He is capable of carrying the ball extremely well," Ludeke said.
Derick Kuun will start as open-side for the Bulls for the first time in three years when they take on the Waratahs.
He last played on the side of the scrum for the team in the semifinal of the Super 14 against the Crusaders in 2007 in Pretoria.
The Bulls team: Zane Kirchner, Gerhard van den Heever, Stephan Dippenaar, Wynand Olivier, Francois Hougaard, Morné Steyn, Fourie du Preez (vice-captain), Rossouw, Pedrie Wannenburg, Derick Kuun, Victor Matfield (captain), Flip van der Merwe, Werner Kruger, Gary Botha, Gurthro Steenkamp.
Replacements: Bandise Maku, Bees Roux, Deon Stegmann, Dewald Potgieter, Heini Adams, Jacques-Louis Potgieter, John Mametsa/Jaco van der Westhuizen.