The reigning A-League champions will face Adelaide United on Sunday and in-form Neumann will feature despite accusations of simulation in last weekend's 3-1 win over Wellington.

Argentine Neumann was alleged to have dived after a challenge from Ben Sigmund, but because he was fouled by the Kiwi defender - who received a red card - the Match Review Panel declared he had no case to answer.

Smith was reluctant to wade into the debate but said defenders must now err on the side of caution.

"There's a very fine line ... so as a central defender, I've got to be wary even if I place a hand on a striker now that he could go down," he told reporters on Friday.

"I guess the answer is not to do it in the first place. My own personal game is to try and be careful of that, try and avoid that and try and get myself in a position that's not going to put me in that scenario.

"That's the way the game is and as players, you need to know that those sort of scenarios are going to happen in a game."

In truth, Brisbane have far bigger concerns than Neumann after a hugely lacklustre performance against Western Sydney Wanderers last Saturday night.

Few times over the past two seasons has the club's passing game fallen apart so badly as it did against the A-League new boys.

"We were probably a bit below par but we've looked at the game," Smith said.

"The biggest thing for us to come out (of it) was the amount of transitions that we had, and the amount of times we gave the ball away.

"We did play our structures, we did dominate the game from a passing perspective, we did look to play. Unfortunately some passes that have stuck in the past just didn't stick last week."

But Smith rejected suggestions the Roar took the Wanderers lightly and warned they were aching to prove that 1-0 loss was an anomaly.

"I don't think there was a touch of complacency. We're never complacent. We take every team for who they are," he said.

"People are questioning things but to be honest, nothing's changed. We're still motivated, we're still determined, we still want to win things, we still want to keep getting better.

"We've never turned up to training not wanting to get better. We've never gone into a game not wanting to get better. That's always been our culture.

"We don't need to focus on what happened last week. Yes, we lost, and we're very disappointed, but for us we really need to concentrate on getting three points on Sunday."

Besart Berisha, Shane Stefanutto and Thomas Broich are all expected to feature against Adelaide after they were cleared of injury.