Mark Hughes felt our winning penalty was harsh on Micah Richards, who was judged to have held Fraizer Campbell.
Robbie Keane beat Shay Given from the spot to secure a 2-1 win and keep us in with a chance of Europe while at the same time ending City's hopes.
"We're disappointed with the decision, it's a poor decision and one that hurt us," Hughes said.
"It was a speculative ball that has gone comfortably to Shay Given and the lad was never closer than 15 yards away from it.
"With five minutes to go we had a real chance to get the winner. We could have been in the mix for Europe."