Bradford City’s unbeaten start to the season is over after they succumbed to the Posh.
Kyle Vassell’s second-half goal settled matters.
Michael Smith teed up Vassell who fired into the top right corner.
James Hanson tried a strike from distance late on, but he could not prevent the Bantams – who were the better team in the first half - from suffering their first defeat of the campaign.
Peterborough move to second in the table, while Bradford slip to eighth-place.