Roar had no answers for a classy Sky Blues attack that extended their lead atop the table by five points courtesy of the four-goal rout in Kogarah.

"It's a real eye-opener for us," Fowler said post-game. "We know what we've got to do.

"We know where we need to be at. And this season, we have been okay, we really have. But for 45 minutes, we wasn't there."

Brisbane entered the clash having appeared to put a disastrous start to the campaign behind them with two wins in their past three outings.

However, Fowler's men fell back to earth with a thud, with their defence opening up too easily on their way to conceding three goals by halftime.

Roar found some resistance after the break but gave up two goals on the counter late in the match before claiming a consolation goal.

It is their easily their heaviest defeat so far under the new coach.

"It's a real wake-up call for us," Fowler said. "When you are playing against top quality players then if you're not on song, it's going to be a long night.

"We (had) 45 minutes of poor play. I wouldn't sit here and throw my players under the bus, because I think they've given us everything this year.

"But that 45 minutes shouldn't be acceptable for anyone, for any manager."

The loss means Brisbane miss their chance at moving into the top six, and instead drop to just one spot above last-placed Central Coast Mariners in 10th spot.

Fowler added: "It's my job and my staff's to pick them up and we go again. There's nothing else we can do. We'll take this on the chin, we'll learn from it, we will."