Dragged into a dog fight in Canberra, the Blues gritted their teeth to snatch an improbable injury-time victory - through a Beauden Barrett drop goal - that may prove their most valuable of the season.
Equalling the 1997 championship-winning side with a 12-match unbeaten run, and locking up Super Rugby Pacific's top seed with one round remaining, did not come easy for the Blues on Saturday night.
When replacement hooker Billy Pollard claimed the Brumbies third try, and Noah Lolesio slotted the conversion to hand the locals a one-point lead with 90 seconds remaining, the Blues seemed toast.
Such is the character the Blues have displayed throughout this season, they found a way to steal the ball back for one final chance and gradually work their way into the Brumbies 22, where they earned a breakdown penalty. Barrett then hit the drop goal while under advantage.
The dramatic finish belied a dour first half but, having emerged out the other side, it bodes well for the Blues with the tension that awaits in the coming weeks.
The Blues victory – achieved without Rieko and Akira Ioane and Tom Robinson - significantly helps the Crusaders, too, as they remain four points clear of the Brumbies in second place.
While the pressure is now off for the Blues in their final round match against the Waratahs in Sydney, the one sombre note will be worries for in-form finisher Caleb Clarke after he left the field in the 52nd minute with what appeared to be a serious hamstring injury following an attempted chase-down of Brumbies halfback Nic White.
Clarke was distressed with the nature of his injury. A long-term stint on the sideline would be a cruel blow, just as Clarke begins to revive his XVs career with a standout season.
Leading 8-7 at halftime the Blues had to survive two maul tries from the Brumbies and a hostile atmosphere to prevail.
Barrett and Roger Tuivasa-Sheck were increasingly influential in the second spell to give the Blues quality direction and punch alongside Stephen Perofeta, while Karl Tu'inukuafe crashing over in the 67th minute proved a telling blow.
Through defensive line speed, breakdown pressure and negative cynical infringing close to their line, the Brumbies had great success disrupting the Blues.
The final penalty count (16-4) told the story of the Brumbies propensity to infringe.
In stark contrast to their two previous matches against Australian opposition, when they notched successive half centuries against the hapless Rebels and Reds, the Blues walked into a fight – and did not always handle it well.
Without their dominant forward platform and fast-paced ruck tempo in the first half the Blues often lacked patience on attack. They became easily frustrated, and battled to convert their territory and possession dominance.
The Brumbies scrambled brilliantly on defence to save three tries by holding up Mark Telea, Clarke and Tuivasa-Sheck over the line.
Blues hooker Kurt Eklund, in prolific try-scoring form this season, was also ruled to have lost the ball while lunging for the line to make it four blown chances for the visitors.
At other times, though, the Brumbies were more than happy to infringe to deny the Blues – conceding 12 penalties in the first half and, thus, copping two yellow cards for repeat infractions.
White did everything within his power to constantly niggle Blues attackers, and largely got away with it.
While the Blues made hard work of crossing for their only try to Barrett just before the break, the Brumbies seized their only genuine chance by stealing a Blues lineout and scoring through former Crusaders loose forward Pete Samu in the third minute.
As fatigue set in and replacements were injected the match opened up somewhat in the final quarter but the Brumbies largely succeeded in forcing the Blues to play the match on their terms.
The upshot, though, is the Blues will now be at home for as long as they remain in the playoffs. Such an advantage cannot be underestimated.
Blues 21 (Beauden Barrett, Karl Tu'inukuafe tries; Stephen Perofeta con, 2 pens, Barrett drop goal)
Brumbies 19 (Pete Samu, Folau Fainga'a, Billy Pollard tries; Noah Lolesio 2 cons)