The Brumbies returned to the victory trail when they claimed a deserved 23-6 victory over the Bulls in Canberra thanks to two second half tries.
The two-time champions fell off the pace in the title race in recent weeks - after suffering back-to-back losses to the Crusaders and Highlanders - but this result moves them to the top of the Australian Conference, although they could slip down to second place if the Waratahs register a bonus-point win over the Cheetahs in Sydney on Saturday.
The Brumbies, who dominated the territorial and possession stakes, outscored their visitors two tries to zero and inflicted the Bulls' first defeat since their loss to the Stormers in their season opener in Cape Town.
The men from Pretoria, who impressed with their free-running style of play in recent weeks, offered little on attack in this encounter and with this loss missed the chance to move above the Stormers at the top of the African Conference One table.
The Bulls made the brighter start and their forwards, in particular, impressed during the early exchanges especially at the set-pieces. Scott Sio endured a torrid time in the scrums and was penalised thrice for illegal scrummaging inside the first 10 minutes.
One of those was within Francois Brummer's goalkicking range and the Bulls were soon 3-0 in front. Christian Lealiifano drew the home side level with a penalty of his own in the 18th minute though and added two more three-pointers from the kicking tee, after the Bulls were blown up for straying offside on defence, which meant the Brumbies led 9-3 at half-time.
The Brumbies made a superb start to the second half when, after launching an attack from a line-out on the edge of the Bulls' 22-metre line, Lealiifano delivered a delightful short pass to Nigel Ah Wong, who breached the Bulls defence with a strong run before crossing for the opening try in the 45th minute.
The hosts continued to dominate as the half progressed and spent large periods camped inside the Bulls' 22. Their dominance was rewarded in the 57th minute when, after the ball was taken through several phases by their forwards, Tomás Cubelli barged over from close quarters.
Lealiifano added the extras, and although the Brumbies upped the ante in the final quarter in a bid to score their third try, which would have secured them a bonus-point try, they didn't achieve that goal. Nevertheless they will be happy that they managed to prevent their visitors from scoring a try.
Tries: Ah Wong, Cubelli
Cons: Lealiifano 2
Pens: Lealiifano 3
Pens: Brummer 2
Brumbies: 15 Aidan Toua, 14 Nigel Ah Wong, 13 Tevita Kuridrani, 12 Robbie Coleman, 11 James Dargaville, 10 Christian Lealiifano (cc), 9 Tomás Cubelli, 8 Jarrad Butler, 7 David Pocock, 6 Scott Fardy, 5 Sam Carter, 4 Rory Arnold, 3 Ben Alexander, 2 Stephen Moore (cc), 1 Scott Sio
Replacements: 16 Josh Mann-Rea, 17 Allan Alaalatoa, 18 Ruan Smith, 19 Tom Staniforth, 20 Blake Enever, 21 Jordan Smiler, 22 Joe Powell, 23 Lausii Taliauli
Bulls: 15 SP Marais, 14 Travis Ismaiel, 13 Jesse Kriel, 12 Jan Serfontein, 11 Bjorn Basson, 10 Francois Brummer, 9 Piet van Zyl, 8 Hanro Liebenberg, 7 Arno Botha, 6 Lappies Labuschagne, 5 RG Snyman, 4 Marvin Orie, 3 Marcel van der Merwe, 2 Adriaan Strauss (c), 1 Trevor Nyakane
Replacements: 16 Bandise Maku, 17 Lizo Gqoboka, 18 Werner Kruger, 19 Jannes Kirsten, 20 Roelof Smit, 21 Rudy Paige, 22 Tian Schoeman, 23 Dan Kriel
Referee: Ben O'Keeffe
Assistant Referees: Will Houston, Ed Martin
TMO: Peter Marshall