Tony Mowbray blasted his defence for a series of self-inflicted wounds as Middlesbrough let a 3-1 lead slip away to lose 4-3 at home to Swansea.
Middlesbrough looked to have victory secure as goals from Marvin Emnes, Barry Robson and Leroy Lita put them 3-1 up after 53 minutes. But the home defence crumbled as Swansea piled forward in a pulsating finish, allowing Scott Sinclair, Ashley Williams and Craig Beattie to add to Nathan Dyer's earlier goal.
A disappointed Mowbray said: "You should never lose grip of a two-goal lead like that but it was all self-inflicted. We have shot ourselves in the foot."
He added: "It comes down to some very poor decision-making on our part."
"When you analyse the game there were huge problems. We had a game plan and to a large extent it worked but then we made some very silly mistakes.
"Now we are looking over our shoulders again. Had we won we could have gone up three, four, five places. Instead we will now have to work very, very hard to make sure we are not looking over our shoulders at the end."
Swansea boss Brendan Rodgers heaped praise on his side for their spirited comeback.
"It was fantastic," he said. "It showed real character and real mental toughness.
"At times this season we have played some fantastic football and we know we have the ability to create goals and score goals.
"When you are 3-1 down it asks you some big questions and we came up with the answers. The supporters can be very proud of the team. I know I am."
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