The veteran defender says John Aloisi's team are equipped to come away from Suncorp Stadium with a positive result despite missing several key men
After opening their season with successive draws against Melbourne Victory and the Central Coast Mariners, Heart suffered a 1-0 defeat away to Perth Glory last time out.
As for their next opponents, John Aloisi's team went down 3-0 to the Roar in pre-season, an unhappy game in which marquee midfielder Orlando Engelaar suffered a broken leg during his first run-out for the club.
With that heavy loss in mind, Wielaert believes the priority for Heart will be to press the possession-orientated hosts, and not allow the likes of midfield maestro Thomas Broich time on the ball.
"I watched the game in pre-season, a game we lost against them," he said.
"It's a very good team, especially on the ball. Against them it's even more important to put good pressure on the ball. Because otherwise you won't have the ball a lot of times in the game. So that's, especially after the last game, very important.
"That's the main thing. And if we have the ball, we have to keep it a little bit longer because if you keep losing the ball as quickly as we did last game, it's hard to win a game. You're only running to get the ball. I think we will do better against Brisbane. We did it (effective pressing) against Victory, they are also very good on the ball and we did very good against them. Some minor changes have to be ready in our head.
"It's not only the players in the back, it begins with the forward players, if they do it right, it's easier for us. That's how we have to see every game, it's a team sport.
"Our structure is good and we'll get better every week, I think."
Heart will be without Patrick Kisnorbo for three weeks after he sustained knee cartilage damage away to the Glory on Sunday.
Wielaert acknowledged his fellow centre-back will be missed, but backed Patrick Gerhardt and David Vrankovic to step up.
"Yeah, but it's no problem," he said when asked about Kisnorbo's absence.
"We have enough players who can fill that space.
"They (Gerhardt and Vrankovic) can both play there. That's the coach's decision, who's going to play with me in the centre."
Captain Harry Kewell returned to training for Heart this week after missing two weeks with a whiplash injury suffered during a head clash in the Round One derby against Victory.
It remains to be seen if the veteran playmaker will be passed fit to play against the Roar, while Engelaar is not expected to make his competitive Heart debut until January at the earliest.
Nevertheless, Wielaert has faith in the resources at Aloisi's disposal.
"Of course, we also miss Harry," he said.
"That's a fact that we miss those guys. Harry is, I think, going to be back pretty soon. Orlando is going to take a little bit longer. We just use the players we can use and make the best of it."