Jamie Proctor's second-half strike kept Bradford in the League One play-off places following a 1-0 win at basement side Crewe.
The striker punished a mistake by defender George Ray to fire home in the 50th minute, with the victory moving Phil Parkinson's side up to fifth.
Teenager Callum Ainley was impressive on his first start for Crewe, who started well. Lauri Dalla Valle seized on a miscontrol from Chris Routis and drilled a shot a yard past the post.
But Bradford turned the screw and Billy Clarke went close with a glancing header from Tony McMahon's cross.
Crewe had two let-offs in the space of a couple of first-half minutes.
First full-back Stephen Darby was put clear by a Billy Clarke pass but slid his shot across the face of goal and Proctor headed over from six yards when it seemed easier to score.
Proctor made amends when he was left in the clear after Ray misjudged a high ball from Nathan Clarke.
Crewe substitute Daniel Udoh, a recent recruit from Ilkeston, went close with a cheeky overhead flick.
But Ben Garratt needed to keep out a late effort from Bradford substitute Steven Davies, who later had a penalty appeal turned down when he appeared to be tripped by the keeper.