Bradford goalkeeper Jon McLaughlin had an afternoon to forget as his own goal set Bury on the way to a comfortable 3-0 win.
The game was only five minutes old when McLaughlin sliced an attempted clearance off Rory McArdle's back-pass into his own net.
It got worse for the Bantams 14 minutes later as Lenell John-Lewis found space on the edge of the Bradford penalty area to drill a well-struck shot into the bottom corner.
McLaughlin made a fine reaction save just before half-time to keep out John-Lewis, but the Shakers stretched their lead on the hour-mark thanks to a swift counter-attack.
Stephen Schumacher was allowed to come forward with the ball and sent in an inviting cross into the path of Lateef Elford-Alliyu and his first-time strike flew into the top corner.