Slazenger went to goals astray in the opening ten minutes and never recovered from this disastrous start.
The visitors eventually found their feet, but failed to find their usual fluid style.
In fact, Slazenger conceded a third goal before Marcus Taylor’s battling midfield display rekindled Slazenger’s spirits.
Nick Webb and Simon Chamberlain combined to produced the first Slazenger score through Andy Foreman.
Unfortunately, once again sloppy defending let Bradford in for their fourth and despite a late consolation goal for Slazenger from Webb, they were left annoyed and frustrated by their performance.
Slazenger firsts have two games at the weekend. Huddersfield first at home on Saturday (1.30pm) and Leeds University firsts in the quarter-finals of the Yorkshire Cup on Sunday (12 noon).