After a goalless first half at Upton Park, Armero concede a spot-kick when he tripped Cameron Jerome in the box.
We put every effort in but could not put the ball into the back of the net
Mile Jedinak converted the resulting penalty to secure Premier League survival for the Eagles and help Tony Pulis’ men seal a club-record fifth straight top-flight win.
“It was stupid penalty conceded by Pablo Armero for the winning goal,” said Allardyce, whose side are 12th in the table and seven points from safety.
“Setting out your plans is all very well, but you cannot make allowances for that.
“He didn’t need to make that challenge and Crystal Palace are set out to take advantage when you make a mistake like that.
“We put every effort in but could not put the ball into the back of the net.
“We had to take chances when they came our way and in that department we failed miserably today.”
Asked about the West Ham supporters’ reaction at the final whistle Allardyce added: “There was no more unhappiness from that fans than I had at Blackburn, Newcastle or Bolton. If you don’t win fans don’t like it, especially at home.”
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