Melbourne City coach John van 't Schip conceded his team did not handle Aaron Mooy's absence in their 3-0 loss to Western Sydney Wanderers.
The marquee midfielder, who starred in the Socceroos' victory over Kyrgyzstan in Canberra, missed an Hyundai A-League game for City for the first time this season on Friday night and Van 't Schip's men failed to cover his absence.
Mooy has started the 2015/16 season brilliantly with two goals and three assists, and Van 't Schip did not shy away from a challenge during his post-match media conference that City are nothing without the 25-year-old.
"Well if you look today, then you're not far from the truth," the Dutch coach said.
"But that's an easy one after a game like this because it was our worst performance, I think, since I'm coach here, at a home game at least."
The contest at AAMI Park turned completely in the Wanderers' favour when referee Peter Green allowed the visitors' second goal to stand.
While an offside flag was raised in the build-up, Green seemingly decided it was not relevant to Federico Piovaccari's goal and Van 't Schip made it clear he was confused.
"If the linesman puts up the flag and he keeps it up quite significant, then players stopped and because of that they scored a goal," he said.
Van 't Schip added his team showed they were "clearly not ready" for their clash with Western Sydney and claimed responsibility primarily rests with him.
In his second stint with the club - first with Melbourne Heart and now with City - Van 't Schip has had almost four years in charge and critics have sometimes claimed he does not have what it takes to produce a championship-winning side.
But he insists he has the ability to get his team back on track after two straight home losses.
"I'm confident and it's important that we're all confident, so not only me, because I can't do it on my own but the players and the supporting staff [too]," Van 't Schip said.