John Aloisi's team raced to a 3-0 lead inside 53 minutes, against the run of play, against a Brisbane Roar side at AAMI Park on Sunday that never quite looked as though it could believe what was happening.

But the dismissal of Heart's opening goalscorer David Williams in the 67th minute completely altered the balance of the game and gave the visitors a sniff.

When Heart captain Fred upended Roar striker Ben Halloran in the 74th minute and Besart Berisha stepped forward to strike the penalty home, it looked a mere consolation for the visitors.

But when Berisha got clear two minutes later to snare his second, the fear in the red-and-white camp was palpable as they dug in for the remaining 15 minutes, a man down and desperate to try to hold out the marauding champion, which was convinced it too deserved to get something out of the game.

In the end Heart managed to hang on and notch only its second consecutive win of the season in the sort of display that will do nothing for the nerves of its small but passionate supporter base.

In the process, Heart lifted itself above the Roar and into sixth place on the ladder and proved, once again, that sometimes it's all about the rub of the green.

Such an outcome couldn't have been predicted in the opening half when the host side looked uninspired and bereft of imagination. But somehow it found itself 2-0 up at the interval with the sort of cushion it was ultimately going to need to ensure itself of the three points.

The last time Brisbane left a rain-sodden AAMI Park after playing Heart, having been trounced 4-1, it vowed never again. Its then coach, Rado Vidosic, declared the performance the team's worst in two years, while captain Matt Smith issued a public apology on behalf of the players.

It seemed the Roar had learnt its lesson, and began this game in a much brighter frame of mind, determined to bury the memory of that shock loss at the earliest possible opportunity.

The Roar is not quite the tiki-taka merchant it was in the days of Ange Postecoglou, where it delivered death by a thousand short passes as it won two championships. Under Vidosic and his successor, Mike Mulvey, it has shown a willingness to be more direct. But old habits die hard and the Roar showed a curious reluctance to shoot in that period of early domination.

The Roar was punished for its hesitancy when its opponent took the lead against the run of play. The first goal came in the 13th minute when Germano found space on the right and delivered a pass to the effervescent Richard Garcia. The former English Premier League midfielder played a clever reverse delivery into the path of Williams, who won the race to the ball to score his third goal of the season.

Brisbane kept trying to make the play and take the game to Heart, which defended stoutly if at times in scrambling fashion, aided by Roar's reluctance to shoot.

But it was Heart that was to strike again, in the 35th minute when it doubled its lead. Josip Tadic ran on to Michael Marrone's through ball as the Brisbane defence appealed for offside. Tadic continued his run and slid the ball past Michael Theo. Referee Allan Milliner proved oblivious to Roar's entreaties, the assistant kept his flag down and the goal stood.

Fred made it three in the 53rd minute when he arrived late and completely unmarked to get on the end of Aziz Behich's cross. It looked like game over - but Roar had other ideas.