For most of the second half the Londoners seemed set to hand the title to Manchester United, having taken a 2-1 lead despite the loss of Joey Barton.
"If we had pulled it off and won the game, it would have been the greatest Premier League performance in history given the significance of the game and the attention focused on it," said Hughes.
"I congratulate City. It is a huge achievement for them. I am sure there will be many more in the future. We touched the well of apprehension they experienced. It was all the more exciting because of that."
In the end though, Hughes accepted that the moment his side knew they were safe quite possibly turned out to be the moment upon which the entire season turned.
"The one criticism is that we understood we were safe just prior to their winning goal," he said.
"Maybe we just switched off.
"I have never been involved in anything like that but Roberto would have to admit he has been lucky today."