Embarrassed Jose Mourinho branded Chelsea's FA Cup fourth-round exit to Bradford "unacceptable" and a "disgrace" as the League One side's giant-killing exploits continued with a phenomenal come-from-behind victory at Stamford Bridge.

League One City brilliantly responded from 2-0 down after 38 minutes to win 4-2 and dump the Barclays Premier League leaders out of the FA Cup.

Chelsea reject Filipe Morais levelled with 15 minutes to go and Jon Stead, the scorer of City's first, teed up Andy Halliday for the winner 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, but he also reserved praise for Bradford after Chelsea's hopes of challenging for an unprecedented quadruple were ended.

"I could find in my bad feelings with the game and with the result space to feel happy for them," Mourinho said.

"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.

"(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, for Chelsea it doesn't happen a lot and I think it's unacceptable to lose against a team from a lower league."

Mourinho conceded defeat when Bradford's fourth went in early in the six minutes of stoppage time, offering Parkinson a handshake which the City boss refused.

Parkinson said: "At that point there was three and a half minutes left. I wasn't getting drawn into that.

"Two goal leads are great, but they can be quickly reduced. We just wanted to stay focused on the result until the whistle went.

"If Chelsea had got one back, even at that late stage, with the world-class players they had on the pitch, they could easily have got a second.

"We wanted to concentrate on what we had to do and see the game through. I was just focused on getting the team right and making sure the lads weren't getting carried away.

"I don't think he meant to be disrespectful. He came into the dressing room afterwards and shook everyone's hand. That was a real touch of class."

It was a memorable day for the Bantams, who beat Arsenal and Aston Villa en route to the 2013 League Cup final, where they lost to Swansea.

"In terms of the performance, the magnitude of beating Chelsea today, that's got to beat them all," Parkinson added.

"It's only slightly sinking in. When we were on the pitch celebrating at the end it did feel a bit surreal, that we've come to the league leaders and scored four goals.

"It's a great feeling and will be remembered in Bradford for a long time, but the rest of the country as well."

At 2-0 down, to goals from Gary Cahill and Ramires, many expected Bradford to buckle, but not Parkinson.

"(We) just wanted half-time to come," he said.

"To get the goal back, and it was a terrific strike from Jon, gave us a real lift and belief.

"Kicking towards our fans in the second half we always felt that we could cause them problems and we certainly did."

Mourinho expects Chelsea to be lambasted for their display, but he also anticipates a response in Tuesday's Capital One Cup semi-final second leg with Liverpool.

He said: "If I was you (the media), I would be very critical with Chelsea, with Chelsea manager, with Chelsea players, but not just that because I think the other guys don't deserve that we forget them. They deserve (praise) after such an impressive result.

"In an ideal world it would affect us in a positive way, not a negative way. We have to win the next match and let's go for it."

Mourinho made nine changes following the midweek draw at Anfield, and with the return and next Saturday's Premier League clash with Manchester City in mind.

He defended his team selection.

He added: "If they cannot play against a team from the Championship or League One or League Two, what do we do? I think the selection was good enough."

Andre Schurrle was conspicuous by his absence.

Mourinho on Friday said the World Cup winner would start, but his omission sparked suggestions the "phenomenal" offer required to seal his departure had been received.

The Portuguese insisted Schurrle, who watched on from behind the dugout, was merely injured.

"He arrived this morning saying he has a little pain in the back," the Blues boss added.

Mobile app users, watch the video here.