Defensive rock Alex Wilkinson vows to improve Sydney defence in A-League

He's the rock Sydney FC hope to build their season on and so far, it's the perfect foundation.

The Sky Blues are yet to concede a goal in the three competitive games veteran defender Alex Wilkinson has played in since joining Sydney FC over the winter, including last week's 4-0 win over the Western Sydney Wanderers.

Their defence was an overlooked aspect of their resounding derby victory, extending their perfect defensive run to four games.

Coach Graham Arnold's side also haven't conceded a goal throughout their FFA Cup campaign.

"You pride yourself on clean sheets. Arnie likes to have his teams defensively well-organised, but we can still be better than what we have been. Western Sydney created a few chances," Wilkinson said.

"It's obviously a good start to show that the structures are in place that things are starting to work without us conceding, but there's a lot of improvement left in us still."

After spending half of last season with Melbourne City, Wilkinson reunited with Arnold in the harbour city after the pair enjoyed plenty of success at the Central Coast Mariners between 2010-12.

The 32-year-old former Socceroo said Arnold was a huge factor in him changing clubs.

"I'm originally from Sydney and my wife's from Sydney, so after being away for four years in Asia, it was nice to be back home. It's good to have that support network," he said.

"And also obviously knowing Arnie and a lot of the players here, it made it a good decision both professionally and personally."

Ahead of Saturday's home-opener against the Mariners, Wilkinson is one of eight players and coaches who have been involved in either camp.

Mariners trio Jacques Faty, Mickael Tavares and Ivan Necevski all switched camps over the offseason and were a part of their 3-3 comeback draw with Perth in round one.

Wilkinson said all three would have a point to prove against their old club.

"Always when you come up against your old club, you want to play well and you want to perform. I'm sure that'll be no different for the guys who left here and went up there," he said.

"I'm sure they'll come out and want to impress."