Sunderland boss Ricky Sbragia admitted his side's performance in the 3-0 loss at West Brom was "unacceptable".
The Black Cats slumped to their fifth defeat in the last six games to leave them still involved in a battle to stay in the Barclays Premier League.
Sbragia said: "We were so poor overall. We seemed to have 11 individuals out there. West Brom played very well and caused us problems and we got what we deserved - absolutely nothing."
He added: "It is hard to explain the way we played. Last week we were committed and worked very hard against Hull and were very difficult to beat.
"We were nothing like that and the players were told in no uncertain terms after the game that it was not good enough. It was not acceptable.
"We didn't turn up. Our decision making was poor. We didn't raise the tempo of the game and the second and third goals were down to bad defending.
"We were well short all over the pitch. I feel sorry for the fans because in the last week they have seen two different sides to us.
"This was the worst side and we look disinterested."
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