Queensy Menig scored a 90th-minute winner as Rovers suffered a 1-0 defeat away to Oldham Athletic.
With the game seemingly destined to end in a draw, the Oldham substitute secured the points as the clock struck 90 with a low left-foot finish past David Raya.
It was cruel on Rovers - roared on by 3,500 terrific travelling fans - who had created the better opportunities during the contest.
In an even first half, Peter Whittingham saw a shot deflect just past the post and Elliott Bennett squandered the game's golden chance when he fired into the side-netting after rounding the keeper.
Raya made a superb save to deny Craig Davies' low drive at the other end.
After the interval, Whittingham saw a long-range effort strike the woodwork and his late corner was almost bundled into his own net by the Oldham keeper.
However, as five minutes of added time went up on the board, Oldham struck the winner. Davies played in Menig, who fired a low shot across Raya and into the bottom right-hand corner.
Ahead of the game, Rovers made two changes to the side that defeated Gillingham 1-0 at Ewood Park a fortnight ago.
Defender Paul Downing was ruled out with a hamstring strain, which meant a return to the team for Elliott Ward, whilst Craig Conway was preferred to Bradley Dack, who dropeds to the bench.
Corry Evans, who helped Northern Ireland qualify for the World Cup play-offs during the international break, missed out with an ankle knock.
There was a familiar face in the Oldham line-up, as Jack Byrne, who made seven appearances for Rovers whilst on loan from Manchester City last season, started for the hosts.
The first real chance of the game went Rovers' way on five minutes. Ward's free-kick was flicked on by Dominic Samuel to Marcus Antonsson, who almost got in behind the Oldham backline, but a covering defender just got back to make a vital challenge as he shaped to shoot.
Oldham registered their first effort on 12 minutes, as Eoin Doyle took on Ward down the left, before seeing his low shot comfortably saved by Raya.
Rovers came close to breaking the deadlock on 14 minutes as Derrick Williams pulled the ball back to Whittingham on the edge of the area, but his first-time shot deflected inches wide of the far post.
At the midway point in the half, Doyle's crisply-struck volley was straight at Raya, whilst Bennett dragged a shot wide at the other end.
On 26 minutes, Rovers ought to have opened the scoring. Conway played an inch-perfect ball over the top to Bennett, who took a touch, rounded the keeper, but then fired into the side-netting with the goal at his mercy.
Rovers continued to threaten, with Samuel seeing a curling shot saved by Johny Placide just past the half-hour mark.
On 35 minutes, Oldham broke quickly from a Rovers corner, with Davies' fierce low drive superbly saved by Raya, who then prevented Doyle from heading home the rebound.
On the stroke of half-time, Byrne played a ball over the top to Gevaro Nepomuceno, who was denied a certain opener by Bennett's last-ditch challenge.
The hosts threatened again straight from the restart, but Davies' near-post effort was comfortably saved by Raya.
Moments later, Rovers were a whisker away from taking the lead, as Samuel saw a shot blocked, before teeing up Whittingham, whose 20-yard strike cannoned off the top of the crossbar.
Byrne then fired an effort from distance just wide of the upright.
In need of a goal, Tony Mowbray made a double change on 57 minutes, bringing on Harry Chapman and Danny Graham for Conway and Antonsson.
Soon after, Richie Smallwood floated a ball over the top for Samuel, whose looping header was plucked out of the air by Placide.
The Oldham keeper almost gifted Rovers the points on 78 minutes, when he failed to deal with Whittingham's inswinging corner, but the ball was hacked clear off the line.
On 83 minutes, Menig dribbled along the edge of the area, before blazing over the bar, but the substitute would snatch the headlines soon after.
Davies played him into the area to his left and he fired a low shot into the opposite corner, past Raya's despairing dive.
Byrne almost added a second in the sixth minute of added time, but Raya made a smart save.
Rovers can now look forward to back-to-back home games against newly-promoted Plymouth and Portsmouth over the next seven days.
OLDHAM ATHLETIC: Placide, Dummigan, Bryan, Clarke, Hunt, Nepomuceno (Menig 67), Fane, Gardner (Omrani 87), Byrne, Doyle (Gerrard 90), Davies.
Subs not used: Ruddy, Wilson, Flynn, Obadeyi.
Goal: Menig (90)
ROVERS: Raya, Caddis, Ward, Mulgrew, Williams, Smallwood (Dack 68), Whittingham, Conway (Chapman 57), Bennett, Antonsson (Graham 57), Samuel.
Subs not used: Leutwiler, Nyambe, Harper, Gladwin.
Booked: Smallwood, Bennett, Chapman, Dack.