Jose Mourinho was "ashamed" by Chelsea's "unacceptable" FA Cup fourth-round exit, but praised Bradford for their giant-killing act in a 4-2 win at Stamford Bridge.
League One City brilliantly responded from two goals down after 38 minutes to dump the Premier League leaders out of the FA Cup.
Chelsea reject Filipe Morais levelled the fourth-round tie with 15 minutes to go and Jon Stead, the scorer of City's first, teed up Andy Halliday for their third eight minutes from time.
And substitute Mark Yeates tucked in a stoppage-time fourth to inflict the Blues' first home loss this season and spark jubilant celebrations from Phil Parkinson's visitors.
Mourinho on Friday said it would be a “disgrace” if his side lost.
After Chelsea’s hopes of challenging for an unprecedented quadruple were ended, he said: “In this moment I feel happy for them. I could find in my bad feeling with the game and with the result space to feel happy for them. I’m honest.
“By another side I feel ashamed and I think the players should feel exactly the same as I feel.
“By one side this is the beauty of football, the beauty of the FA Cup. It happens more in the FA Cup than any other country.
“(But) I repeat the word that I used yesterday in case we lost – it’s a disgrace. A sporting disgrace, but it’s a disgrace.
“I know in the history of this competition it happens to every team now and again.
“For me it’s the first time and I think it’s unacceptable to lose against a team from a lower league.”