Bradford City failed to make it a hat-trick of League One victories as Dominic Samuel headed home the only goal for the previously pointless visitors at Valley Parade.
Late City pressure came to nothing although Corry Evans and Peter Whittingham were fortunate not to concede penalties for handling as they cleared the danger.
Stuart McCall made one change for the visit of relegated Rovers, Shay McCartan replacing Alex Jones and playing just behind the front two of Dominic Poleon and Omari Patrick.
The Northern Ireland prospect, however, blotted his copybook when he was booked for diving in the area during a first half which produced minimal chances for either side.
Late challenges also earned yellow cards for City's defensive midfield man Timothee Dieng and Rovers frontman Samuel.
The Reading product soon made a bigger impression after the break, stooping to head home from six yards after Craig Conway whipped in a cross from the left.
City made a triple substitution in the 70th minute, strikers Charlie Wyke and Alex Jones and winger Paul Taylor entering the fray, but McCall's side were unable to muster a grandstand finish as they fell to a first defeat of the season.
McCall said “The goal is a deflection. It’s headed against Tom Field, hits his face and goes in the opposite corner.
“We certainly didn’t do enough going forward to win the game. But I thought there was nothing in it second half.
“It was nice to have that run but last year when we drew four games, it would have been better for us to have won two, lost two.
“That’s football but it’s not a big thing for me. It’s disappointing to lose but you’ve got to some time.”
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The return from a slight hamstring tear of striker Charlie Wyke was one of the few bright spots for City, who had gone through the previous season unbeaten at home in the league.
Their starting front two made little impression on a robust Rovers defence and it would be foolish to bet against Tony Mowbray's visitors from making a swift return to the Championship.