Wednesday have leaked goals from every conceivable bad mistake in the book this campaign and the Owls boss says that it is just not acceptable.
Speaking after the game with Luton at the weekend, he also slammed some of the so-called experienced players at the club for not doing their jobs once they were on the pitch.
He said: "The defending this season has been bad. You are powerless on the touchline because when the players cross over that white line, some players who do some good things can make some very costly mistakes.
"They are a great bunch of lads but they won’t win you anything. We only have one game left, we have fifteen players out of contract in the summer and people are slowly coming round to the realisation that we don’t have a good enough squad, despite having players of experience here."