The wheels haven't quite fallen off the City bandwagon in the past two weeks, but two defeats in a row have seen them drop a few gears and lose pace with the league leaders.

Last week's loss to Newcastle was a strangely muted display by a team whose approach in the previous three months had been characterised by its commitment and ability to find goals and get results when things weren't going their way.

Van 't Schip knows that if they approach the game against Victory in the same frame of mind then there will only be one outcome for City.

"I was disappointed about the team spirit, it wasn't as it should have been. If you don't have the right spirit, or we are not connected, then every game is going to be difficult," he said on Friday.

"Newcastle should get credit for winning the game, but looking at our team that's where we lacked compared to a few weeks ago when we played Western Sydney Wanderers at home [when City got up 3-2 through a late Harry Novillo goal].

"We need to get stronger ... in becoming that fighting team as well. If you really want to become the team that is on top week in and week out, that's another step we have to improve.

"Tomorrow is a great exam ... it's a special game both teams. It's about who really wants it tomorrow. That's the main thing. We have played a lot of games against each other, looking at the statistics there is a high percentage of us winning games even in the Heart period."

One of van 't Schip's key decisions will be whether to start Alex Wilkinson, the Socceroo centre back who only joined the club this week.

Wilkinson has not started a game since late December. But having signed him – and given the lack of defensive options with injuries to Connor Chapman and Aaron Hughes and suspension for Jacob Melling – the likelihood is that he will be thrown in at the deep end, perhaps alongside Patrick Kisnorbo and Jack Clisby in a back three, with Osama Malik in a holding midfield role lending support to the defence.

"He has shown a good physical appearance, he has kept on training, I think the break was good for him, he had been playing for a long time," van 't Schip said of Wilkinson.

"We had a good look at him, he has trained on his own the past few weeks. It's not that he is coming out of not doing anything.

"Bringing in Alex gives us another option to look how we can reinforce and implement him into the line up. It's just a plus to what we are doing.

"Anthony Caceres is back [from suspension]. Malik can play in the midfield, Jason Trifiro has been doing well in the past few weeks."

Building that team spirit is not easy in a squad that has chopped and changed as much as City's these past few weeks, with several comings and goings during the January transfer window.

"At this moment we are in a second building phase this year compared to the team we started with. I am happy with the players who have come in and with the possibilities that we have," the Dutchman said.

"It's about showing we can deliver, its about gelling again ... making sure that we can grow in the coming weeks.

"We have enough time, I am confident in the players we have to grow. The top teams are going to be playing each other over the coming weeks ... with a good run you can really gain spots and points.

"They [the new signings like Wilkinson, Caceres and Nick Fitzgerald] know we are eager to keep them, they are happy being in this environment and club. So now it's a question of focusing on what we have to do."

The key for City is likely to be holding firm at the back – not easy for a club that has only kept one clean sheet in 18 games – and the form of Bruno Fornaroli, the Uruguayan striker who has been in such good form this season.

"He's scoring, but his influence on the pitch is big in his working, linking up and giving the example, keeping the opponents busy with his play and his runs," the coach said.

City will help to raise awareness for adolescents and young Australians living with cancer, highlighting the 'Support Joey Appeal' on Saturday night by donating at least a dollar for every attending fan at the derby. They will hold a fundraising auction, as well as giving supporters of both teams the opportunity to support the campaign through donations, match day activities and social media.

The appeal is being run by CanTeen, with Age soccer writer Michael Lynch's son Joey a primary beneficiary.