Bradford lost their unbeaten record with a 1-0 at home to Peterborough.
Kyle Vassell scored the winning goal in the 57th minute, the fourth goal of the campaign for the Posh striker.
Substitute Michael Smith collected a long diagonal pass from Shaun Brisley and supplied a pass to the unmarked Vassell, who scored with a right-foot shot into the far top corner of the net.
The goal came two minutes after Bradford's influential central defender Andrew Davies was led off the field with what looked like an arm injury following a collision with his own keeper as Jordan Pickford came off his line to punch clear. The lengthy on the field treatment contributed to nine minutes of stoppage time.
Peterborough had the better chances of an evenly fought first half, with Pickford diving to turn away Connor Washington's shot in the 14th minute.
There was a narrow escape for Bradford in the 41st minute when Joe Newell's inswinging corner was punched away by Pickford. The ball rebounded off Ricardo Santos on to the post and Santos headed wide from the rebound.
Bradford's best effort came in first half stoppage time when Ben Alnwick, on trial with City in pre-season, dived full length to turn away Billy Knott's 15-yard shot, but they rarely looked like saving the game once Posh had gone in front.