The Reds had gone into the break 1-0 up after Matty Fryatt gave them a lead their first-half performance deserved.
But goals from Alex Baptiste, Rudy Gestede and Jordan Rhodes left Forest in shock as Rovers scooped the points.
Stuart Pearce made two changes to the side that drew at Watford on Tuesday night. Out came Ben Osborn and Eric Lichaj and in came Fryatt and Jack Hunt. Henri Lansbury, available again after serving a one-match suspension in midweek, was named on a bench which also included Jamie Paterson, Danny Fox and Jamaal Lascelles.
Both sides had forays into each other’s final third at the start of the half, but Forest created the first genuine chance on 13 minutes when Hunt did brilliantly to get away from Ben Marshall near the Rovers right corner flag. The full back took the ball along the line and into the area but, with options in the middle, he could only roll his cross straight at Jason Steele.
Roles were reversed four minutes later when Marshall tricked his way past Hunt, cutting in from the left and buying himself space to shoot. The ball looped up off Michael Mancienne and behind for a corner, which Forest cleared.
Michail Antonio continued his excellent start to his Forest career with two goals at Watford, and he demonstrated his threat for the first time of the afternoon on 22 minutes when he eased his way past Baptiste down the left. The winger passed to Britt Assombalonga, who turned quickly in the area before seeing his shot blocked by Corry Evans.
The Reds had asserted their authority by this stage and nearly capitalised on panic in the Rovers defence on 28 minutes. A long ball over the top was poorly dealt with by the visitors and Fryatt brought it under control. His shot from the edge of the area was blocked and Antonio could only fire the ball over the bar on the follow up.
Forays into Forest’s final third had been rare for Rovers, and when they ventured forward on 32 minutes they were nearly caught out on the break. Assombalonga led it, latching on to a long ball and neatly passing it to Fryatt. The striker spread the ball out to Antonio on the left who got to the corner of the area before shifting the ball on to his right. Assombalonga had made a run into the middle but Antonio’s pass came too late and the ball rolled through the crowd of bodies in the area and out for a goal kick.
For all Forest’s possession they had struggled to carve Blackburn open, and it was after a scrappy spell on the edge of the Rovers box that David Vaughan was presented with a chance to score from a free-kick in a dangerous position.
Evans was booked for his foul on Assombalonga but Vaughan could only fire the ball into the wall, with Harding’s effort being blocked on the follow-up.
But a minute later The Reds had the lead their dominance deserved. Robert Tesche picked out Assombalonga in space with an excellent pass, and the striker had time to give himself an angle to shape a superb right-footed effort at goal with the outside of his boot. Cruelly, the ball hit the base of the post, but Forest’s frustration was short-lived as Fryatt reacted quickly to tap it home from close range.
And it was the home side who ended the half on the front foot, Burke robbing Shane Duffy and playing the ball to Assombalonga 20 yards out. The striker flicked the ball away from his marker cutely before smashing it just over the bar on the half-volley.
Forest deserved to end the half further ahead, and they perhaps should have done when Tesche picked out Assombalonga with an excellent through ball. The latter had displayed excellent movement to receive the pass but pacy full back Marcus Olsson did just enough to put the striker off after he had burst through one-on-one with Steele. He dragged the ball wide of the far post with his shot and Blackburn will have been relieved to hear the half-time whistle.
They came out fighting for the second half, however, and came close to scoring an unorthodox equaliser when Marshall’s overhit cross put Darlow on the back foot. The keeper held on well, but was left helpless five minutes later as a Blackburn throw-in caused havoc in the Forest box. The ball ran free for Rhodes amid the scramble but The Reds managed to ride out the danger.
Both sides made changes after the hour mark, with Lansbury replacing Fryatt for The Reds and Gestede coming on for Rovers’ Evans, joining Rhodes up front.
And the visitors’ attacking intentions bore fruit on 66 minutes. Darlow committed himself to dealing with Marshall’s cross from the left but failed to do so. The ball came out to an unmarked Baptiste in the box who had plenty of time to generate enough power to blast the ball home from eight yards.
Forest’s response was immediate, Antonio getting to the byline and testing out Steele’s handling with a vicious low cross. The keeper held on well, but he was called in to make an even better save a minute later.
Hunt found himself in possession in acres of space down the right, got to the byline and cut the ball back perfectly for the onrushing Lansbury. The midfielder struck the ball well first time but Steele made an excellent save low down.
Forest kept the move alive, however, and Lansbury left the keeper helpless with his next effort. The substitute turned two defenders superbly in one slick movement before curling the ball towards goal. It crashed off the post and was cleared to safety.
Determined not to let their hosts reassert their dominance, Ryan Tunnicliffe led by example by winning a 50-50 with Tesche in the middle before embarking on a strong run into Forest territory. He managed to get a shot away on the edge of the area but Mancienne did well to get across to block the shot.
The visitors continued to threaten, however, and Darlow had to exhibit quick feet to get back on to his line and tip the ball over the bar after Lee Williamson had struck it down into the turf amid a goalmouth scramble.
But Blackburn had the lead with 15 minutes to play when Williamson’s cross found Gestede at the back post, whose powerful leap allowed him to head the ball beyond Darlow and into the net.
And it got worse for Forest two minutes later when Mancienne failed to deal with an awkward ball over the top, allowing Rhodes to gain control. The striker toyed with Forest’s defence in the area before squeezing the ball into the far corner.
Pearce sent Paterson on for Tesche as a shellshocked Forest sought a way back into the match, and the midfielder was presented with an opportunity three minutes after coming on when he latched on to an excellent Antonio pass down the left. Paterson cut on to his right foot in the area but saw his shot blocked.
The visitors pressed again, however, and Gestede should have had his second when he nodded the ball wide from Conway’s dinked cross.
Frustration was creeping in for Forest, who had half chances through Assombalonga and Antonio as full-time neared.
But Blackburn weren’t letting up, Gestede firing the ball into the side-netting from range before Tom Cairney drew an excellent save from Darlow following a Rovers breakaway in the first of four added minutes.
There was just enough time for Burke to fire the ball wide after bursting into the area before the referee called time on a disappointing afternoon for Pearce’s men.
Forest: Darlow, Harding, Mancienne (c), Wilson, Hunt, Burke, Tesche (Paterson 80'), Vaughan, Antonio, Fryatt (Lansbury 62'), Assombalonga
Subs not used: De Vries, Lichaj, Fox, Lascelles, Blackstock
Goal: Fryatt 37'
Steele, Baptiste, Hanley (c), Duffy, Olsson, Williamson, Evans (Gestede 63'), Tunnicliffe, Cairney, Marshall (Conway 78'), Rhodes (Varney 87')
Subs not used: Eastwood, Henley, Kilgallon, Dunn
Goals: Baptiste 66', Gestede 75', Rhodes 77'
Booking: Evans 35'
Referee: Oliver Langford
Attendance: 27,345 (1,043 away)
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