MELBOURNE Victory coach Ange Postecoglou accepted responsibility for his side's 4-2 loss to fierce rivals Adelaide United on Friday.
Victory fell behind to an early goal just two minutes in before striker Andrew Nabbout scored his fourth goal of the campaign to equalise.
However, sloppy defending and lapses in concentration saw Adelaide race to a 4-1 lead with three goals inside 11 minutes, all in the first half.
Marcos Rojas got a goal back directly after half-time but it was only a consolation, as United avenged their 2-1 loss when the two sides met in October.
Having seen his team concede four goals in 32 minutes, Postecoglou took the blame for the defensive leaks.
"I probably got team selection wrong. It wasn't my greatest coaching night so I deserve what I get. My performance was pretty ordinary," Postecoglou said.
"We had a really poor first half defensively and we paid the price for it.
"I thought our football was still decent in the first half, but just that defensively we weren't desperate enough and positionally we weren't great.
"Adelaide were too good for us tonight. Our fragilities are for us to address, but you've got to pay credit to Adelaide."
With Mark Milligan on international duty and defender Adama Traore out injured, Melbourne were left depleted at the back.
Postecoglou said the lack of defensive options hampered the Victory, but refused to use that as an excuse.
"We had to re-shuffle things again at the back tonight and missing Adama was probably a bigger blow for us," Postecoglou said.
"We had Diogo (Ferreira), Petar (Franjic) and Sammy Gallagher as three of the back four and I don't think any of them are settled in their positions yet, so it was probably too much to ask of them.
"We weren't good enough to cover the exits of the players we have."
Friday's loss marked the first time in six games the Victory have tasted defeat after claiming 13 points from a possible 15.
Postecoglou did not feel the heavy loss to Adelaide was a reality check for his team, who had climbed to third on the table.
"Does that have any far reaching implications? Time will tell, but I'm still fairly positive about where we are heading," Postecoglou said.
"We will get Milligan, (Archie) Thompson and Traore back next week which is fairly significant."