AFC Wimbledon ended Rovers' four-match winning run with a 1-0 win at Ewood Park.
Kwesi Appiah scored the only goal of the game on 16 minutes, smashing a crisp strike into the top corner from inside the area.
Rovers pushed for an equaliser after the break, but twice had penalty appeals for handball waved away, before substitute Bradley Dack saw a header saved on the line.
It was a disappoitning day for Tony Mowbray's men, who had gone into the game on the back of four straight wins over Bradford, MK Dons, Rochdale and Scunthorpe.
But despite dominating the game for long spells, they were unable to find the cutting edge required to break down the Dons defence.
Ahead of the game, Rovers made one change to the side that won at Scunthorpe in midweek, with Craig Conway returning to the team in place of Rekeem Harper, who was ruled out with a thigh injury.
Rovers came flying out of the traps and registered the game's first attempt inside 30 seconds. Dominic Samuel picked up possession and tried his luck from outside the area, forcing George Long to parry the ball away.
The hosts saw plenty of the ball in the early exchanges, but it was the visitors who broke the deadlock on 16 minutes with their first meaningful attack.
Appiah broke into the box and as Richie Smallwood attempted to make a challenge, the ball fell kindly to the Dons striker, who smashed a shot into the top left corner.
The visitors threatened at the midway point in the half, as Dean Parrett let fly from long range and his shot took a slight deflection as it flew just past the post.
Rovers ought to have levelled moments later. Conway delivered a sublime cross from the left and Samuel sent a free header over the bar from close range.
Just past the half-hour mark and Rovers were forced into a change, as Conway, holding his hip, was unable to continue and he was replaced by Dack.
And the substitute came close to an equaliser on the stroke of half-time. After breaking into the box, Dack opted to stay on his feet when he could have gone to ground under a challange, before forcing a smart save from Long at his near post.
Rovers had a lucky escape six minutes into the second half, as Andy Barcham and Parrett both saw shots blocked from inside the area, before Mowbray made his second change, bringing on Danny Graham in place of Smallwood.
The switch added some extra attacking impetus to Rovers' play and they twice had penalty appeals waved away soon after, as first Samuel and then Dack saw shots strike the arm of a Dons defender in the box, but on both occasions the referee remained unmoved.
Straight up the other end, Appiah again looked to find the top corner with a curling shot from the edge of the box, but Raya got across his goal to keep it out.
On 66 minutes, Dack delivered a cross from the left and Samuel's glancing header fizzed over the bar.
Rovers made their final change soon after, bringing on Harry Chapman for Marcus Antonsson, and the substitute almost set up the equaliser on 77 minutes.
Chapman sent over a superb cross from the right and Dack's deflected header was somehow kept out by Long right on the Dons goal-line.
Rovers pushed and pushed in the closing stages, with Wimbledon happy to hit on the break, but the hosts were unable to find a way through.
ROVERS: Raya, Caddis, Ward, Mulgrew, Williams, Conway (Dack 33), Smallwood (Graham 55), Evans, Bennett, Antonsson (Chapman 69), Samuel.
Subs not used: Leutwiler, Downing, Whittingham, Gladwin.
Booked: Bennett, Evans
AFC WIMBLEDON: Long, Fuller, Oshilaja, Nightingale, Francomb, Appiah (McDonald 75), Trotter, Barcham (Forrester 75), Parrett, Hartigan, Taylor (Robinson 80).
Subs not used: McDonnell, Sibbick, Kaja, Egan.
Goal: Appiah (16)
Booked: Nightingale, Fuller
Attendance: 10,833 (369 Wimbledon fans)