The Trotters get their season under way this weekend when the Bantams head to the University of Bolton Stadium for the first round of the Carabao Cup.
The 32-year-old striker joined the Valley Parade side in 2018, scoring 11 goals in all competitions for the Yorkshire side in the 2018/19 season.
The Irishman spent much of last campaign at Swindon Town, initially on loan from Bradford. And it proved to be a successful spell for both the Robins and the player, with Doyle moving to Swindon permanently in January and ending the season as League Two's top goalscorer.
He signed a three-year contract with the Trotters this summer and has been given the number nine jersey for the new campaign.
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