City have struggled in their big games this season, copping a 3-0 home defeat to the Glory while also losing to Melbourne Victory and Sydney FC.

"We've been working a lot on mentality. Obviously, there's tough stages through the game where you're fatigued and you're tired, but you've got to find that extra bit of oomph to get up and keep battling," Brillante said.

"And we definitely have the talent and the players there to perform and score goals; it's just the mentality that's been lacking for us."

Brillante said there had been a focus collectively and individually at training on maintaining concentration in games.

"I think that comes from training and being focused and switched on in training every day, prepping up to the game and telling yourself not to be lazy when you might have to run back an extra 20m to help the team, and those little things make a big difference on game day," he said.

With Saturday night's clash between second and third shaping as a tantalising affair, Brillante emphasised the importance of starting fast and hitting the scoreboard early.

"Obviously, it being second v third makes it a bigger occasion and these are the games that players need to step up and show what they're capable of," Brillante said.

"And this is the difference between being one of the top teams in the league, and so I think on Saturday we have to come out firing, especially after the last game against Perth."

There will be a curtain raiser to the game, with City and the PFA hosting the 'Oz Football Aid' match, raising money for Rural Aid. Two dollars from every ticket will go towards the charity.

The two teams, captained by Craig Foster and Anthony LaPaglia, will feature celebrities, media personalities and 15 former Socceroos and Matildas with more than 500 international caps between them.

Australian Associated Press