The Brumbies all but sealed a place in the Super Rugby play offs when they beat the Rebels 39-17 with a bonus point in Canberra.
The Brumbies went to the top of the Super Rugby standings but they have played two more matches than their New Zealand and South African rivals.
The Australian Super Rugby teams come back from their break with just one match to play before the play offs.
The Brumbies play the Force in their final regular season match and the Reds play the Waratahs.
The Brumbies top the Australian Super Rugby Conference with a five point lead over the Reds and they have a 100+ points buffer in points differential over the Queenslanders.
For the Reds to top the Australian Conference they would need to beat the Waratahs by 120 points and hope the Force upset the Brumbies without the Force conceding a bonus to the Brumbies.
Missing five current Wallabies, the Brumbies shook off their first-half lethargy to storm away from the Rebels after leading 10-3 at halftime to score four second-half tries and win convincingly.
It is the first time the Brumbies have qualified for the Super Rugby finals since winning the southern hemisphere provincial series in 2004.
Former South African winger Clyde Rathbone scored a brace of tries with other tries from Scott Sio, Henry Speight, Colby Faingaa and Zack Holmes.
Replacement scrum-half Ian Prior kicked three conversions and fullback Jesse Mogg a long-range penalty.
Stand-in captain and Wallabies hopeful Nic White left the field in the ninth minute clutching his shoulder as Wallaby coach Robbie Deans looked on ahead of naming Tuesday's final Test squad to face the British and Irish Lions.
The Rebels, without their two Wallabies James O'Connor and Nick Phipps and sidelined injured forwards Scott Higginbotham, Hugh Pyle and Jarrod Saffy, closed to 13-10 after a try by winger Tom English against the run of play.
But the Brumbies hit back with four consecutive tries to seize control of the match and clinch a four-try bonus point.
"I know that we are proud of winning the conference and we get into the playoffs for the first time in a long time but our coaching staff are really proud with the way the bench and those who haven't had a chance for a long time, really stood up and took their chance tonight," Brumbies coach Jake White said.
"We knew it was about preparation going into this game and this group has been together for two years and as soon as they lifted their intensity and started some go-forward we got some pay."
There are only two Australian-only matches this weekend as New Zealand and South African teams have a three-week break for Test rugby.
The Brumbies play their final regular season match against Western Force in Perth on July 13, while the Rebels are at home to New Zealand's Highlanders on July 12.
Final Score Brumbies 39 (10) Rebels 17 (3)
Tries - S.Sio, C Rathbone 2, H.Speight, C.Faingaa, Z.Holmes
Pen - J.Mogg
Con - I.Prior 3
Tries - T.English, P.Alo-Emile
Pen - J.Woodward
Con - J.Woodward
Referee: Rohan Hoffmann
Assistant Ref 1:Steve Walsh
Assistant Ref 2:Matt O'Brien
TMO : George Ayoub
1. Scott Sio , 2. Siliva Siliva , 3. Dan Palmer , 4. Leon Power , 5. Sam Carter , 6. Scott Fardy , 7. Colby Faingaa , 8. Peter Kimlin , 9. Nic White (c) , 10. Matt Toomua , 11. Clyde Rathbone , 12. Pat McCabe , 13. Tevita Kuridrani , 14. Henry Speight , 15. Jesse Mogg
Replacements , 16. Josh Mann-Rea , 17. Ruan Smith , 18. Etienne Oosthuizen , 19. Jordan Smiler , 20. Ian Prior , 21. Robbie Coleman , 22. Zack Holmes.
1. Nic Henderson , 2. Ged Robinson , 3. Laurie Weeks , 4. Cadeyrn Neville , 5. Luke Jones , 6. Jordy Reid , 7. Scott Fuglistaller , 8. Gareth Delve (c) , 9. Nic Stirzaker , 10. James Hilgendorf , 11. Lachlan Mitchell , 12. Rory Sidey , 13. Mitch Inman , 14. Tom English , 15. Jason Woodward
16. Pat Leafa , 17. Paul Alo-Emile , 18. James King , 19. Tim Davidson , 20. Luke Burgess , 21. Angus Roberts , 22. Kimami Sitauti