The A-Leagues' newest club has made an instant impact, with Auckland FC scoring a 2-0 victory over Brisbane Roar in a sold-out home debut at Mt Smart Stadium.

Both the sky and the Mt Smart Stadium stands were blue as Auckland FC arrived in the competition, their picture-perfect debut finishing with a scoreline to delight the sold-out crowd.

Harry Van Der Saag's eighth-minute own goal gave the Black Knights an early lead on Saturday, before Logan Rogerson's composed second-half finish secured the result.

"It's amazing," coach Steve Corica said.

"There's been a big build-up to this game … the boys were looking forward to it and we knew the crowd would get right behind us, which they did."

This was a day that went completely to script for the hosts and league chiefs.

Not only could coach Steve Corica be happy with three points, but Auckland FC's billionaire majority owner Bill Foley would be delighted with the bumper support from Aucklanders.

The thumping 24,492-strong attendance was vindication too for head office, which awarded the licence and pushed on with the club's entrance, injecting some much-needed vitality to the competition.

That figure was just south of the best-ever crowd for an A-League Men club's inaugural game, showing the appetite for the sport in New Zealand's biggest city.

There was also raucous support across the ditch in Western Sydney, where Wanderers active supporter group the Red and Black Bloc unveiled an enormous "RBB" tifo in the stands before kick-off.

It covered a sizeable chunk of the 27,496 fans packed into the stadium to watch the local derby against Sydney FC, featuring the A-League debuts of Spanish star Juan Mata and Brazilian Douglas Costa.

But striker Patryk Klimala upstaged the big-name imports by leading the Sky Blues to a 2-1 win over the Wanderers with an assist and the decisive goal.

Foreign strikers usually take a while to acclimatise to the ALM, but already Klimala looks the goods and the Polish forward was a thorn in the Wanderers's side throughout the 90 minutes.

The former Celtic frontman set up Joe Lolley for Sydney's opener, then turned in the winner in the 63rd minute.

Coach Ufuk Talay hopes it is a sign of things to come, with a front line boasting Klimala — as well as Lolley and Costa on the wings — shaping as the ALM's most dangerous.

"A striker is always going to be judged on goals," Talay said.

"If he's scoring goals, I think he's going to be confident, he's going to be happy.

"That's why we brought him in here. It's not the goals that he just gives us … the work he does off the ball really helps us.''

Costa was solid — his cross was the catalyst for Klimala's match-winner — and the Brazilian gave the packed crowd a glimpse of his fleet-footed skills.

Mata was not brought into the game until the second half and the Spaniard was unable to really stamp his authority in a stint that lasted a little over half an hour — the most he has played in nearly 18 months.

The only downside for Sydney was a late straight red card for Max Burgess for a lazy tackle on Ben Holliday.

In Saturday's other game, Melbourne City beat the Jets 1-0 in Newcastle.

AAP