A disappointed Bantams boss Phil Parkinson was forced to admit that his players hadn't risen to the challenge of facing the league leaders after City lost out at table-toppers Burton Albion.
A deflected first half strike from former Bantams loanee Mason Bennett gave Burton the interval lead.
An unfortunate own goal from Ben Williams after the break then doubled the hosts' advantage before a Mark Duffy tap-in minutes later sealed the win for the Brewers.
Rory McArdle netted a consolation goal via a glancing header from a Tony McMahon corner in injury time but the effort did nothing to lighten Parkinson's mood after the game.
Parkinson said: "We have to accept we were second best today (Saturday). We were second best all over the pitch.
"We started poorly and got punished for it.
"Without playing well in the first period, we’ve actually had some good chances ourselves to get back into the game. We needed to take one of them to give us a lift.
"We have missed the target today on a couple of occasions when we should really have tested the ‘keeper.
"Although we are disappointed with the way we played, there hasn’t been too much in the game. Ben (Williams) hasn’t had too many saves to make.
"The first two goals haven’t gone in our favour with the bounce of the ball off our players and then Greg (Leigh) cramped up around the time of their third.
"He couldn’t continue so we had to take him off shortly afterwards."
City began the game at the Pirelli Stadium using a diamond shape in midfield but the introduction of Mark Marshall and Wes Thomas at the break saw Parkinson revert to a more standard 4-4-2 formation for the second period.
Parkinson added: "We looked at things this week in the build up to the game as we know we haven’t been good enough away from home this season against the top teams.
"We also looked at teams who had done well against Burton recently and we decided to go that way (with the diamond formation in midfield).
"Teams do change systems throughout the season, and it is formation that served us well at times last year.
"It hasn’t worked for us on this particular occasion, and I have to take responsibility for that.
"As much as we talk about formations, however, there were also far too many below standard performances from us.
"With the diamond in the first half, we created chances. With the 4-4-2 formation in the second period, we conceded twice.
"Sometimes too much can be made about systems and formations – you still need players to play well, especially when you are coming to top of the league.
"We have some players coming back for next weekend (vs Peterborough United) but we need to re-group and go again after this one because it has been extremely disappointing.
"I feel for the supporters coming down here to a place where we have so many good memories after the Play-Off semi-final of three years ago.
"To come up second best in so many departments this afternoon is not good enough.
"The Bradford fans are used to seeing a lot better than they did today and I have to accept that."