The Bulls charged past the Highlanders 35-18 in Super 15 rugby on Saturday to retain control of the South African conference and move second overall as Springboks Pierre Spies and Morne Steyn reached milestones.
Skipper Spies scored one of the Bulls' four tries in his 100th Super Rugby game and Steyn became the Pretoria team's most capped player in the competition with his 117th appearance.
Center JJ Engelbrecht went in for the first try inside two minutes as the dominant Bulls capitalised on their first possession and wing Akona Ndungane's 60-meter breakout just before halftime maintained their control.
Spies scored early in the second and replacement halfback Jano Vermaak eventually secured a bonus point with the fourth try two minutes from time. Vermaak's sniping break to the left corner in the 78th minute came just as the Bulls appeared to have missed out on the extra point that moved them level with Brumbies, and above the Australian team having won one more game.
The Bulls are now 8-3 and have won five straight games in South Africa to be two points off leaders and defending champions the Chiefs.
Steyn kicked three conversions and three penalties for 15 points in his record-breaking game as he passed the 116 Super Rugby caps for the Bulls by Victor Matfield and Danie Rossouw.
Replacement No. 9 Fumiaki Tanaka and hardworking center Tamati Ellison crossed late for the bottom-place Highlanders of New Zealand, who struggled against the Bulls' set-piece and slipped to one win and 10 losses this season.
Engelbrecht's opener came from the Bulls' first attack after the Highlanders turned over the ball from the kickoff. He eventually scooped up a scrappy pass out on the left wing to go over as the three-time champions capitalized early.
Steyn kicked three penalties to opposing first-five Colin Slade's two to push the Bulls further ahead before Ndungane's breakaway in the 38th. The right went blazing downfield to score from a disputed pass by Engelbrecht, which appeared to go forward before Ndungane scooped it up, but was ruled good by the television match official.
Spies marked a century of games with the third try seven minutes into the second half, charging over from close range on the short side and taking the Bulls 30-6 ahead.
The Highlanders also had wing Tino Nemani and prop Chris King sin-binned within 10 minutes of each other early in the second to make their task much harder. Tanaka slipped through in the 72nd for the Dunedin-based visitors. Ellison scored with the last act of the game and in the left corner after Vermaak had given the Bulls their bonus point.
Bulls 35 (JJ Engelbrecht, Akona Ndungane, Pierre Spies, Jano Vermaak tries; Morne Steyn 3 conversions, 3 penalties), Highlanders 18 (Fumiaki Tanaka, Tamati Ellison tries; Colin Slade 2 penalties, Hayden Parker conversion). HT: 23-6.