An injury time winner from Bristol Rovers' man-of-the-moment Jonson Clarke-Harris saw the hosts snatch all three points following a dramatic conclusion to City's contest at the Memorial Stadium.
With Rovers leading 2-1 just before five minutes of additional time at the end of the match, Nathaniel Knight-Percival swooped to volley home an equaliser for the Bantams from a Jacob Butterfield cross.
Knowing that realistically only wins will do at this stage of the season, Gary Bowyer's men pushed forward for a winning goal in the lengthy period of added-on time that followed.
As City drove men forward, however, Rovers pounced on the counter-attack and Clarke-Harris, who was recently named Sky Bet League One Player of the Month for March, netted to seal a heart-breaking, and barely deserved, defeat for Bowyer's side.
Ahead of the late drama, Lewis O'Brien had fired City into a fifteenth-minute lead following a purposeful start to the encounter from the Bantams.
With City looking largely in control going into the break, Rovers frustratingly found a leveller seven minutes before the interval when Clarke-Harris headed home in space from a Liam Sercombe corner.
Into the second period, a fine strike from distance by Rovers' Ollie Clarke had looked set to be the match-winner until the two interventions from Knight-Percival and then Clarke-Harris.
Sean Scannell, Josh Wright and Jack Payne were all handed started berths, as Bowyer made three changes to his starting XI.
David Ball missed out through injury, with Jermaine Anderson and Billy Clarke moving down to the bench.
Against a host side who looked to be off the pace initially, City made a bright start to the contest and created the first real scoring opportunity eight minutes in.
A short corner involving Butterfield and O'Brien eventually saw Payne with the ball at his feet in the box.
Payne fired low for goal, but the effort was held by Rovers 'keeper Jack Bonham.
The Bantams did move into the lead soon after, however, after good work in the box by Payne.
The Huddersfield loanee fired dangerously across the six yard box after neat foot-work moved him into a pocket of space in the area.
Rovers blocked the effort from Payne, but O'Brien nipped in as James Clarke delayed his clearance and the City midfielder fired home into the far bottom corner.
City looked on top at this stage, and O'Brien threatened again minutes later when his driven strike across goal was cleared in the middle by Tony Craig.
Rovers responded with efforts from distance by Tom Nichols and Sercombe but, in truth, the home team were creating little of note and City seemed comfortable as the half progressed.
The recalled Wright fired over from the edge of box following another short City corner routine, while Eoin Doyle saw an angled drive from inside the area just after the half hour point blocked away by Craig.
Shortly afterwards, Scannell showed nice feet to get clear in the box and away from Tareiq Holmes-Dennis, but the winger's pull-back couldn't quite pick out Doyle and O'Brien in the middle.
With City looking to have things under control then, it was certainly disappointing to see them concede in perhaps avoidable fashion as time ticked down towards the break.
Clarke-Harris managed to get away from his marker in the box from a Sercombe corner to power home a header past O'Donnell.
From nowhere then, Rovers had somehow got themselves level going into the break.
They threatened again from another Sercombe set-piece before the interval, but Knight-Percival was able to clear after Tom Lockyer had glanced a header across goal from the near post.
After overcoming that blow of conceding, though, it was City who came closest to scoring early after the restart.
O'Brien saw a cross-come-shot blocked behind by Lockyer, with Scannell then touching the ball wide after Knight-Percival had headed down into the mix from the resulting Butterfield corner.
Rovers could have edged their noses in front shortly afterwards, however, when Clarke-Harris beat O'Donnell to a Sercombe cross into the box.
Clarke-Harris rose highest to head towards goal - but the effort dropped onto the top of City's crossbar and behind.
Rovers then engineered half chances on the attack, but Paul Caddis was in position twice to clear the danger as Sercombe and Clarke-Harris looked to get shots away in the box from separate attacks.
Sandwiched in between those openings, Abu Ogogo fired comfortably over from the edge of the area after a James Clarke long throw-in into the box was cleared out to him.
Back came the Bantams with opportunities of their own though.
Butterfield had a drive from distance held by Bonham. City threatened once again minutes later when a Butterfield cross was headed down by Knight-Percival.
Scannell looked to fire home from inside the box but his goal-bound effort was blocked away.
With around twenty minutes of the contest to play, O'Brien then saw a low drive from just inside the box claimed by Bonham by his near post.
The match looked up for grabs moving into its final quarter, and it was Rovers who edged in front for the first time in the afternoon.
Clarke had already tested O'Donnell with a low drive from distance a minute or so earlier when he took aim from around twenty yards out.
The midfielder's drive whistled past O'Donnell's dive and into the far corner to fire Rovers in the lead.
City's response to going behind was to introduce George Miller and Billy Clarke into the action from the bench.
Miller was involved seven minutes from the end of normal time when he hit the bar from a Paudie O'Connor cross - but the sub striker was flagged offside.
The Bantams knocked on the door once more soon after.
After getting joy from a number of short corners in the match, City played it short again - something that eventually saw Payne in plenty of space just inside Rovers' area.
Payne drove the ball across the six yard box but O'Connor wasn't quite able to scramble the ball home from close range.
The pressure did pay off for City in the final minute of normal time though.
A Butterfield driven cross into the box - following yet another short corner - found the run of Knight-Percival perfectly and the defender expertly volleyed into the far corner.
The goal and the signal of five minutes of over time that followed soon after sparked a late siege on the Rovers goal by the Bantams.
Butterfield fired inches wide of the far post with a drive from outside the box seconds into injury time.
As City pushed men forward, though, they left themselves open to the possibility of a counter-attack from the hosts.
Three minutes into injury time that worry was sadly confirmed when Holmes-Dennis crossed low into the middle from the left.
Clarke-Harris connected sweetly with the delivery and his strike for goal found the net past O'Donnell's drive.
The goal was unfortunately the final act in an eventful second period, and it left City again empty-handed after more than holding their own in yet another recent fixture.
Match line ups, stats and updates from the Bristol Rovers fixture can be found via our Match Centre - HERE.