Kick-off is at 15h30 and the action will be broadcast live on SuperSport.
Van Rooyen was forced to make one change to the starting line-up, with Len Massyn coming in for Francke Horn at No 8.
It's Massyn's first start of the Rainbow Cup campaign, with Horne missing out after picking up an ankle injury in the Emirates Lions' heart-breaking last minute defeat to the DHL Stormers last weekend.
Jordan Hendrikse gets another start in the No 10 jersey after a very good debut last week, while Burger Odendaal will again lead out the Pride of Jozi against their neighbours to the north.
“Consistency is the main thing for us; consistency in training, consistency in attitude and consistency in team selection," said Van Rooyen.
"We are facing the team at the top of the log and it will be tough. We have a lot of respect for the Bulls."
Emirates Lions: 15 EW Viljoen; 14 Rabz Maxwane, 13 Wandisile Simelane, 12 Burger Odendaal (captain), 11 Courtnall Skosan; 10 Jordan Hendrikse, 9 André Warner; 8 Len Massyn, 7 Vincent Tshituka, 6 MJ Pelser, 5 Reinhard Nothnagel, 4 Ruben Schoeman, 3 Carlu Sadie, 2 Jaco Visagie, 1 Sti Sithole. Replacements: 16 PJ Botha, 17 Ruan Dreyer, 18 Asenathi Ntlabakanye, 19 Willem Alberts, 20 Emmanuel Tshituka, 21 Morné van den Berg, 22 Fred Zeilinga, 23 Manuel Rass.
Date: Saturday 22 May
Venue: Emirates Airline Park, Johannesburg
Referee: AJ Jacobs
Assistant Referees: Aimee Barrett-Theron, Morne Ferreira
Television Match Official: Marius Jonker
TV: SuperSport Rugby and Grandstand channels