After a record 36-game undefeated streak Brisbane have now suffered back-to-back losses and their first defeat at home since January 2010 after being overpowered 2-1 by an impressive Melbourne Heart unit at Suncorp Stadium on Friday night.
The defending Hyundai A-League champions were a disjointed mess, while the Heart were in sync from the outset, executing a measured game-plan to perfection.
The victory takes the Melbourne side into third place with 15 points, only five short of league leaders Brisbane.
Brisbane were without midfield maestro Thomas Broich and looked a less imaginative side for his absence, unable to work their way into the game until late in the second half after already conceding two in the first.
Melbourne's early possession and field position yielded the lead in the 12th minute when Jonatan Germano lost his defender at the corner and directed his header past Theoklitos with precision.
The second came in the 27th, when the hosts were dispossessed on the halfway point and Germano flew down the sideline, curling in the perfect cross for Mate Dugandzic, who showed presence of mind to square back for Eli Babalj to finish a brilliantly worked goal.
After Mitch Nichols reduced the deficit to one in the 78th, hot foot Besart Berisha had the chance to deliver a draw with three prime-position free kicks, but Clint Bolton and his defenders cleared the first two and Erik Paartalu headed over the box after breaking through with the third.
The Heart's first attacking foray came in just the second minute, with Rutger Worm scything down the left, and their confident start grew into a dominant opening half, in which they registered five shots on target to Brisbane's one.
In the 20th minute Nichols executed a fluid turn to lose his defender and create space to drive at goal, but typical of the performance on the night, the opportunity ended with miscommunication and an errant pass.
Nichols and Issey Nakajima-Farran both had long-range strikes covered by Clint Bolton midway through the first stanza, but the upturn was short-lived for the hosts.
The Heart ended the first with a flurry of quality chances to add a third, but the shots went wide or the Roar defence scrambled and the score stayed locked at 2-0 at the interval.
After the break it was more of the same from Brisbane, with a bit of extra frustration, while the Heart stayed composed with the lead.
The 19-year-old Nicholas Fitzgerald, who was highly impressive in his debut for Brisbane, looked to be in on goal in the 74th minute, but referee Kris Griffiths Jones saw enough jostle to pull back the play.
Just as Brisbane looked to be resigned to defeat, substitute Kofi Danning took the ball on the top of the area and shot into the area like a rocket, dribbling to the base and then squaring back for a trailing Nichols to tap home.
The Roar surged and surged through the final 15, finally finding some of their cohesion, but were unable to convert their opportunities.
Brisbane Roar 1 (Nichols 78)
Melbourne Heart 2 (Germano 12, Babalj 27)