Speaking to the Press Association after the match, the City boss said: "There is a ball bouncing and you hit it as hard as you can against him or go into a tackle. "He hasn't got it in him to hit a backpass with his right foot from there.
"I have the hindsight of video. "At the time I didn't think it was a backpass and I definitely didn't think it was a penalty.
"The contact was outside the area and Vaughan has gone to ground. He was the most surprised person in the ground when it was given a penalty.
"But rather than complaining we should look at ourselves, we let the decisions affect us and didn't respond in the right manner.
I thought we played really well. We set out with what we wanted to do. Our reaction, myself included, has cost us the game.
"It's been a rubbish week but that is part of getting better. It's about getting on with it."
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