The Bulls won the 2009 Super 14 rugby series in Pretoria on Saturday, beating the Chiefs 61-17.
The Bulls scored eight tries to two to win by a record margin before a capacity crowd of 55,000 at Loftus Versfeld Stadium.
The 2007 champions are undefeated at home this year.
The half-time score was 34-7.
Meanwhile, the British & Irish Lions have won the first game of their South African tour, beating an invitation team 37-25 in Rustenburg.
The half-time score was 18-10.
It was the first of six warm-up matches before the first Test against South Africa in Durban on 20 June.
At Twickenham, the Barbarians beat England 33-26.
England play Argentina at Old Trafford in Manchester on 6 June and again on 13 June in Salta, Argentina.