Led by inspirational captain Mark Milligan, Victory were simply everywhere, defending from the very front.
A raucous crowd of 29,843 kept their spirits high throughout, creating the intense atmosphere predicted by Victory coach Kevin Muscat.
Muscat, who celebrated wildly after Broxham's third goal, becomes the first man to captain and coach a team to an A-League championship.
The success is Victory's first in five years and gives the club an A-League record befitting their off-field stature.
An injury to defender Jacques Faty did not help Sydney, who hobbled from the ground within the opening half hour.
In the first 30 minutes, the Sky Blues had completed just 24 passes and shortly after they were behind.
Gui Finkler cushioned Barbarouses' firm cross into the path of Berisha, who expertly controlled and lashed past Vedran Janjetovic.
After goals in two grand final wins with Brisbane Roar, the big-stage Albanian proved his worth yet again.
It was a goal that Victory deserved and finally sprung Sydney FC to life.
Only in first-half injury time did captain Alex Brosque have his side's first shot of the match.
It nearly got worse for the Sky Blues, with two brain fades in two minutes from Matthew Jurman that nearly gifted Milligan and Barbarouses a second.
The injection of Shane Smeltz gave them a new route to goal but it was golden boot winner Marc Janko that had Sydney's best chance.
With 15 minutes remaining, the Austrian marquee's free header was well saved by Lawrence Thomas.
But with seven minutes left on the clock, Victory's Kiwi livewire poked home a loose ball in the box to make the game safe.
Carl Valeri was needlessly sent off after a second yellow card with three minutes remaining for kicking the ball away but there was still time for more celebration.
The stoppage time introduction of Archie Thompson brought the Victory crowd to life once more, but he was upstaged by Broxham.
The Victory utility latched onto Fahid Ben Khalfallah's through-ball to claim a third goal and send the crowd into raptures.
A-League final highlights
THE OPENING GOAL: Besart Berisha with an absolute showstopper in the 33rd minute. The fiery Albanian controlled the ball beautifully then unleashed a powerful strike that beat two defenders and the keeper.
THE KEY MOMENT: Victory only had a 1-0 lead in the 79th minute and tension was starting to really build when Nikola Petkovic had a good chance to equalise after a foul on the cusp of the box. His shot went close, but sailed over the crossbar.
THE GAME-CHANGING INJURY: Sydney FC defender Jacques Faty limped off the field in the 18th minute with tears in his eyes, having tweaked a hamstring. Victory players had surprisingly refused to put the ball out.
THE STAT THAT MATTERED: Sydney FC managed just 24 completed passes in the opening 30 minutes.
THE TALKING POINT: Berisha drew blood in the 14th minute with a wayward elbow to Matthew Jurman's head. Jarred Gillett brandished a yellow card. A disgusted Graham Arnold seemed to think the referee got the colour wrong, while locals were outraged to see any card.
THE BLOW UP: Hard to single out just one. There was no shortage of spite and Sydney FC striker Marc Janko set the tone early when he screamed at Mark Milligan for staying down after a challenge.
THE CARDS: Carl Valeri was sent off in the 88th minute when he collected his second yellow card. Six other players were given yellow cards.
CROWD: 29,843
THEY SAID IT: "If people don't think this is the best club in Australia, well, they should shut up," BERISHA soaks up his third A-League title.
-AAP
