West Ham United have a mountain to climb in two weeks time after losing the home leg of their UEFA Cup first-round tie 1-0 to Palermo.
The Sicilian side snatched the priceless away goal in the last minute of the first half - and in controversial circumstances.
West Ham claimed the ball had gone out of play but Palermo played on and Aimo Diana picked out Andrea Caracciolo to slot his shot past Roy Carroll.
West Ham dominated possession and Carlos Tevez enjoyed their best chance with a volley from Bobby Zamora's cross.
But the Hammers will need to be much sharper in front of goal in a fortnight's time - they must score at least twice to keep alive their hopes of a European campaign.
Pardew's men had rediscovered a pace and rhythm to their play that was missing in the 1-1 draw with Aston Villa on Sunday but they wasted three early corners and Tevez could not pick out Lee Bowyer's charging run into the box.
The Italians hardly enjoyed any notable possession in the opening 15 minutes - but still came closest to scoring when David Di Michele turned Anton Ferdinand in the box only to scuff his shot wide.
Nigel Reo-Coker sent two drives over the bar before West Ham worked their best chance of the half. Zamora latched on to Bowyer's ball down the left and picked out Tevez with a pin-point cross. The Argentinian's low volley was saved brilliantly by keeper Alberto Fontana.
Then, just a minute before the interval West Ham were stung when Diana found Caracciola to give Palermo the lead.
Carroll saved West Ham from falling further behind when he rushed off his line quickly to block Caracciola, who had escaped the offside trap to latch on to a long ball.
Matthew Etherington came on for Bowyer and pulled back a neat ball into the box - but it was agonisingly just behind Tevez and Zamora.
Benayoun tried to fashion a shooting chance but was closed down quickly. Tempers frayed when Palermo keeper Alberto Fontana through-ball behind claiming he had been fouled by Benayoun - only for the referee to award a corner.
Pardew then made a double substitution with 15 minutes remaining - swapping Tevez and Zamora for Marlon Harewood and Carlton Cole.
Harewood hit the post with his first touch of the ball from Benayoun's cross. Etherington kept the attack alive but was booked for diving in the box.
West Ham pelted balls forward but nothing fell right for them in the box and they now face a major challenge to turn the result around in a fortnight's time.
