The Blues produced their best performance of the season to beat the Brumbies 30-16 in Canberra on Saturday and open the door for the Reds.
The result means that the Brumbies have to rely on other results going their way later on Saturday, as the Reds could potentially knock them out of contention for the play-offs with a bonus-point win over the Waratahs.
The Brumbies have built their campaign this season on solid defence and tactical kicking, but it was these disciplines that let them down against a Blues side that played with refreshing enthusiasm.
The Blues seized the early initiative, playing a fearless brand of rugby that gave a glimpse of what could have been for the Auckland side this season.
Their talented backs got an opportunity to impress as they sent it wide and looked to expose some chinks in the determined Brumbies defensive system, and managed to get over the gainline quite easily.
Once they were within striking distance the Blues' forward pack showed took over and some good driving play eventually resulted in lock Liaki Moli bashing his way over for the opening try.
The home side looked rattled and a couple of wayward kicks gave the Blues further opportunity to put them under pressure.
The visitors needed no second opportunity and another flowing movement saw impressive outside centre Francis Saili hit some space before working it out to Daniel Braid who charged over in the left corner for their second try which put them 14-0 up once converted from the touchline by Piri Weepu.
The situation demanded a response from the Brumbies and they promptly delivered.
After managing to secure some possession in Blues territory for the first time in the match they were rewarded with a penalty from the boot of flyhalf Zack Holmes which was followed by a brilliant individual effort by Henry Speight who stepped his way past a few defenders like they were not there and dived over for a stunning try.
Holmes added another penalty shortly afterwards and just like that the Brumbies were right back in it at 14-13.
However, the Blues continued to play with freedom and a telling run from electric fullback Charles Piutau sparked another fluent attacking movement which saw them sweep into the Brumbies 22 with some great interplay.
With the defence stretched left wing Hadleigh Parkes was able to stroll over for their third try which gave the visitors the 21-13 advantage they took into the half-time break.
The Brumbies looked to tighten things up in the second half and they were first to score when Jessie Mogg landed his second penalty attempt, but the Blues hit back with two of their own from Weepu which stretched the lead to 27-16.
A passing showe meant that the cold conditions became wet as well, which turned the last 20 minutes of the match into something of a grind, and it was the visitors who finished with momentum as they pinned the Brumbies in their own half.
A penalty from Michael Hobbs put the seal on a well-rounded performance and a comprehensive victory which ends a disappointing season on a positive note for the Blues.
The Brumbies will be concerned with their error-rate and now face an anxious wait as their prospects this season are to be decided in Brisbane with the Reds aiming to snatch the top spot in the Australian conference at the last possible minute.
Man of the match: There were a number of Blues players who impressed. The Braid brothers worked hard and outside centre Francis Saili had some great touches but the best player on the pitch was fullback Charles Piutau who threatened every time he touched the ball.
For the Brumbies:
Pens: Holmes 2, Mogg
For the Blues:
Tries: Moli, D Braid, Parkes
Cons: Weepu 3
Pens: Weepu 2, Hobbs
Brumbies: 15 Jesse Mogg, 14 Henry Speight, 13 Andrew Smith, 12 Pat McCabe, 11 Joe Tomane, 10 Zack Holmes, 9 Nic White, 8 Ben Mowen (captain), 7 Michael Hooper, 6 Peter Kimlin, 5 Sam Carter, 4 Scott Fardy, 3 Dan Palmer, 2 Stephen Moore, 1 Ruaidhri Murphy.
Replacements: 16 Anthony Hegarty, 17 Scott Sio, 18 Leon Power, 19 Fotu Auelua, 20 Ian Prior, 21 Tevita Kuridrani, 22 Robbie Coleman.
Blues: 15 Charles Piutau, 14 Sherwin Stowers, 13 Francis Saili, 12 Ma'a Nonu, 11 Hadleigh Parkes, 10 Michael Hobbs, 9 Piri Weepu, 8 Luke Braid, 7 Daniel Braid, 6 Chris Lowrey, 5 Steven Luatua, 4 Liaki Moli, 3 Charlie Faumuina, 2 Kevin Mealamu (captain), 1 Tony Woodcock.
Replacements: 16 Tom McCartney, 17 Tevita Mailau, 18 Andrew Van der Heijden, 19 Peter Saili, 20 Alby Mathewson, 21 Orene Ai'i, 22 Lachie Munro.
Referee: Jonathon White (New Zealand)
Assistant referees: Ian Smith (Australia), Julian Pritchard (Australia)
TMO: Matt Goddard (Australia)