Serfontein & Fouché face fitness tests
Bulls scrumhalf Jano Vermaak will make a 100th Super Rugby appearance on Saturday if he takes to the field in his side's match against the Sharks in Durban.
The former Cats (11 caps) and Lions (62 caps) player will represent the Bulls for the 28th time and become South Africa's 22nd centurion at this level.
He has been named on the bench for the derby clash, but should see action in what is anticipated to be a very bruising affair.
Bulls coach, Frans Ludeke, who earlier in the day signed a three-year extension as head coach, made some minor changes to the team what outplayed the Highlanders last weekend.
Two are in the backline.
Bjorn Basson returns to the left wing berth and swap places with Lionel Mapoe, who will move to the bench.
It will also be a milestone for Bjorn Basson, with the try-scoring ace playing in his 50th match of Super Rugby, having also represented the Cheetahs nine times.
The most experienced Super Rugby midfielder in the country, Wynand Olivier, is also back at No.12, with Jan Serfontein moving to the bench.
Both Serfontein and replacement flyhalf Louis Fouché have niggles and a final call on who will play in Durban will be made later.
Ludeke also refreshed his front row - with Werner Kruger and Dean Greyling returning in place of Frik Kirsten and Morné Mellett.
Willie Wepener also rotates with Callie Visagie on the bench.
Bulls: 15 Jürgen Visser, 14 Akona Ndungane, 13 JJ Engelbrecht, 12 Wynand Olivier, 11 Bjorn Basson, 10 Morné Steyn, 9 Francois Hougaard, 8 Pierre Spies (captain), 7 Dewald Potgieter, 6 Deon Stegmann, 5 Juandré Kruger, 4 Flip van der Merwe, 3 Werner Kruger, 2 Chiliboy Ralepelle, 1 Dean Greyling.
Replacements: 16 Willie Wepener, 17 Frik Kirsten, 18 Grant Hattingh, 19 Arno Botha, 20 Jano Vermaak, 21 Louis Fouché/Jan Serfontein, 22 Lionel Mapoe.
Date: Saturday, May 25
Venue: Kings Park, Durban
Kick-off: 19.10 (17.10 GMT)
Referee: Jonathan Kaplan (South Africa)
Assistant referees: Craig Joubert (South Africa), Reuben Rossouw (South Africa)
TMO: Deon van Blommestein (South Africa)