The Brumbies extended their lead in the Australian Super Rugby conference when they beat the Waratahs 23-6 in Canberra.
The Brumbies scored both tries in the match - one in each half - and at the same time prevented the Waratahs from crossing their tryline.
The victory ended three match losing streak for the Brumbies against the Waratahs who will host the Brumbies in Sydney after the June break on July the 7th.
The result looks to have come at a cost for the Brumbies though as Christian Lealiifano was stretchered from the field after the final whistle with a suspected broken right ankle in a splint.
The early medical diagnosis is that Lealiifano will miss the rest of the season due to the ankle injury.
The Brumbies are now in a strong position to win the Australian Conference as all of their remaining matches are in Australia or New Zealand.
The Brumbies lead the Waratahs by nine points and they are gauranteed four points next week as they have a bye while conference rivals the Waratahs play the Bulls and the Reds play the tournament leading Chiefs.
There was not much in it at the break, but the Brumbies outplayed their near neighbours in every department and kept the Waratahs scoreless in the second half despite losing skipper Ben Mowen to a yellow card with eight minutes left.
The smaller Brumbies pack easily won the battle up front, allowing halfback Nic White to control the match in an outstanding individual performance that will surely see him win Wallaby selection for the June Test matches.
"It was a really important game for us, particularly with the conference system," Mowen said.
"We're reasonably pleased but we're not getting too far ahead of ourselves."
The Waratahs started well and had all the early ball and territory but were unable to take advantage, and the home side struck first with a 10th minute Lealiifano penalty from almost right in front.
However, hands in the ruck from Brumbies lock Scott Fardy allowed Waratahs scrumhalf Brendan McKibbin to equalise just seven minutes later.
The Brumbies weathered the early Waratahs storm and gradually worked their way back into the match with their hard running loose forwards beginning to make inroads around the rucks and mauls.
Another Lealiifano penalty made it 6-3 before McKibbin's second three-pointer tied it up three minutes from halftime.
But in the first minute of injury time, Brumbies winger Henry Speight burst down the sideline and brushed off Berrick Barnes and Adam Ashley-Cooper to score beside the posts and send the home side into the break leading 13-6.
The Brumbies came out firing after halftime and battered the Waratahs line in the opening few minutes, centre Andrew Smith eventually capitalising when the Waratahs ran out of defenders after multiple phases of attack.
Lealiifano converted from 10 metres in from the sideline to make it 20-6 then made it safe for the Brumbies with his third penalty in the 71st minute.
The Waratahs never looked like bridging the gap.
"I can cop it when you get outplayed out there, but not when you get out-willed," Waratahs captain Benn Robinson said.
"That's a pretty disappointing performance from us -- there were a few key areas where they definitely got on top of us."
Final Score Brumbies 23 (13) Waratahs 6 (6)
Tries - H . Speight, A. Smith
Con - C. Lealiifano 2
Cards - B. Mowen (yellow)
Pen - B. McKibbin
Referee: Chris Pollock
Assistant Ref 1: James Leckie
Assistant Ref 2: Richard Goswell
1. Ben Alexander, 2. Stephen Moore, 3. Dan Palmer, 4. Scott Fardy, 5. Sam Carter, 6. Ben Mowen (c), 7. Michael Hooper, 8. Fotu Auelua, 9. Nic White, 10. Christian Lealiifano, 11. Joe Tomane, 12. Pat McCabe, 13. Andrew Smith, 14. Henry Speight, 15. Jesse Mogg,
Replacements:,16. Anthony Hegarty, 17. Ruaidhri Murphy, 18. Peter Kimlin, 19. Ita Vaea, 20. Ian Prior, 21. Robbie Coleman, 22. Tevita Kuridrani.
15. Adam Ashley-Cooper, 14. Atieli Pakalani, 13. Tom Kingston, 12. Tom Carter, 11. Peter Betham, 10. Berrick Barnes, 9. Brendan McKibbin, 8. Wycliff Palu, 7. Jono Jenkins, 6. Dave Dennis, 5. Kane Douglas, 4. Sitaleki Timani, 3. Sekope Kepu, 2. Tatafu Polota-Nau, 1. Benn Robinson.
Replacements: 16. John Ulugia, 17. Jeremy Tilse, 18. Dean Mumm, 19. Lopeti Timani, 20. Rocky Elsom, 21. Sarel Pretorius, 22. Daniel Halangahu.