BLOEMFONTEIN: Former champions the Bulls overwhelmed the Cheetahs 51-19 despite finishing the match with only 13 players.
Scrum-half Francois Hougaard was red carded for a dangerous tackle midway through the second half at Free State Stadium and flank Jacques Potgieter got a late yellow card.
Bulls outscored the home team by six tries to one after leading 31-12 at half-time and fly-half Morne Steyn passed the 1000-point mark in the annual championship with another superb goal kicking exhibition that netted 21 points.
The three-time champions are fielding a new-look team this year after several retirements, most notably of iconic lock Victor Matfield, while other stars like scrum-half Fourie du Preez and lock Bakkies Botha have moved abroad.
This display of raw forward power and clinical backline finishing would have thrilled Matfield, watching from the sideline in his part-time role as a television analyst for Pan-African channel SuperSport.
Props Dean Greyling and man of the match Werner Kruger were among the try scorers and they formed a strong front row with Chiliboy Ralepelle as the Bulls followed up a five-point home win over the Coastal Sharks last weekend.
The South African derby was staged before a large crowd in a tense atmosphere and Cheetahs flank Heinrich Brussow had his scrumcap ripped off during a mini-brawl as time ticked away.
"We worked hard for each other and that is what carried us to victory in a tough battle. Morne (Steyn) is a special athlete and his superb goal kicking always lifts us," said stand-in skipper Ralepelle.
Cheetahs captain and hooker Adriaan Strauss promised to cut out ill discipline after conceding 11 penalties last weekend when losing narrowly to the Golden Lions in Johannesburg, but there was little improvement.
"We spent the whole first half defending against a tactically superior team and surrendered possession too easily. Despite this setback I am positive about our tour of Australasia," he said.
Teenage fly-half Johan Goosen kicked an early penalty to give the Cheetahs a lead they held for five minutes, but Greyling barged through for a try on 10 minutes to give the Bulls a lead they never lost.
Fullback Zane Kirchner dotted down in first half stoppage time for the bonus-point fourth try and any hopes of a Cheetahs revival when Strauss went over were quickly extinguished as JJ Englebrecht scored an intercept try.
Kirchner (two), loose-head Greyling, tight-head Kruger, left wing Bjorn Basson and replacement back Englebrecht scored the Bulls tries with Steyn converting all six and kicking three penalties.
Goosen slotted four penalties and converted the Strauss try for the Cheetahs, who face a Brumbies team guided by former Springbok coach Jake White in Canberra next Saturday while the Bulls host the Auckland Blues in Pretoria.
BULLS 51 (Dean Greyling, Werner Kruger, Bjorn Basson, Zane Kirchner 2, JJ Englebrecht tries; Morne Steyn 6 con, 3 pens) def CHEETAHS 19 (Adriaan Strauss try; Johan Goosen con, Goosen 4 pens). Referee: Craig Joubert (RSA)