The Sky Blues have conceded just eight goals in 18 games, at an average of 0.44 per game. It is an extraordinarily miserly rate that they are determined to continue over the last nine rounds of the regular season.
Western Sydney Wanderers registered the best return in the competition's history when they conceded just 21 goals in 27 games, at 0.77 per game, in the 2012-2013 season.
Sydney could concede 12 goals in the last nine rounds and still beat that, but they obviously want to continue as they have done so far, and also remain unbeaten.
Wilkinson, 32, is the leader of the defence and he has a rich history of being a key man in stone-wall back fours.
He was in the Central Coast Mariners team that conceded just 24 goals in 27 games, at 0.88, in the 2011-2012 season, and the Korean side Jeonbuk Hyundai Motors that gave up only 22 goals in 38 games, at 0.57, in winning the 2014 K-League.
Wilkinson told The World Game the ability to defend as incredibly well as Sydney have done, comes down to five key factors - accountability, preparation, fitness, attitude and belief.
"Preparation is the big thing. We play with basically the same approach every week, but obviously every opponent is different so you've got to tweak certain things in games according to the opponent's strengths and weaknesses," Wilkinson said.
"Everyone must know exactly what their job is and the quality of the preparation is clear from how well the new boys have come in recently and done their job.
"The boys have a fantastic attitude. They put the team first and worry about their individual performances second and are prepared to do that extra work for the team.
"And the belief has gone through the roof. We wanted to win things this year and as the season has gone on and the results have continued to come the belief has grown and grown.
"Every single player believes we're not going to lose a game and that we're going to go through and win the grand final."
Wilkinson said strength and conditioning coach Andrew Clark had made the players the fittest they've ever been.
"The fitness level, for the way we want to play, has got to be extremely high," he said.
"It takes a lot of work out there on the field and Andrew has done a brilliant job of getting everyone fit enough to be able to keep running.
"The fitness levels have got to be high, but you've also got to want to buy into the way we play.
"Everyone in the side, not just the back four, is accountable defensively, because 'Arnie' (Graham Arnold) is adamant about every player in every position doing his job.
"If just one player doesn't do his job, the opposition can beat the pressure quite easily, so everyone has got to work together.
"The boys up front and the midfielders are working really hard to press teams high up the park and not give them too much time on the ball and that makes our jobs as central defenders and fullbacks much easier, because a lot of the time the boys are winning the ball before it gets to us.
"When we're going forward and we're in our attacking half, Arnie gives the players freedom to do what they want, but as soon as we lose the ball everyone has got a job to do.
"There are no ifs or buts about it from a defensive point of view and if you don't do your job he'll bring in someone else."
Arnold was, of course, the coach of the Mariners team in 2011-2012 and Clark was the strength and conditioning man there as well.
Wilkinson said Arnold's approach had made it possible for the Sky Blues to continue to defend well despite major forced changes to the defensive line-up during the season.
Matt Jurman, Seb Ryall, Rhyan Grant, Michael Zullo, Aaron Calver, David Carney, Jordy Buijs and Wilkinson have all been used in the back four.
"Arnie's very big on the structure of the team and what he wants everyone to do both, when we have the ball and when we don't have the ball," Wilkinson said.
"He drills it into the boys at training, the structure and the positioning he wants, and over the past month Aaron, David and Jordy have all come into the team at various stages and fitted in pretty seamlessly.
"Arnie gets them ready with video work and extra tactical work so that when they step on the field, even if they haven't been playing week in, week out, they know exactly what's required and it's great for the depth of the team to have so many options."
