The opening day of the season ended in disappointment for Rovers as Charlton Athletic returned to London with all three points.
Rovers had plenty of the ball at a sunny Ewood Park, but created little on the day against the south Londoners, who did a job in East Lancashire.
Ben Purrington gave the visitors the lead from a couple of yards out just before half time, but Rovers responded and forced an equaliser early into the second half through an own goal from goalkeeper Dillon Phillips.
But just when you thought Rovers would go on to win the game, Mowbray's men were dealt a sucker punch with 13 minutes remaining as Lyle Taylor flicked home what was to be the winning goal.
Tony Mowbray started four of his five new signings for the opening day clash, with Christian Walton, Bradley Johnson, Stewart Downing and Sam Gallagher all earning berths in the XI.
But Tosin Adarabioyo wasn't named in the squad having had limited time training with the players having only signed on Wednesday.
Rovers were having the better of the opening stages, with Gallagher and then Bradley Dack firing wide of the target in the opening 10 minutes.
Downing almost got himself a debut goal midway through the half, but an excellent run and cross from Gallagher down the left just evaded the former England man, who was lurking in the box.
Charlton weren't offering too much going forward, but Walton had to be alert 10 minutes before half time to beat away Lyle Taylor's left-footed drive when the visitors did venture upfield.
But with their next chance Lee Bowyer's side took the lead through Purrington, who sneaked in at the back post to prod into the roof of the net after a dinked cross from the right by Jonny Williams.
Soon after and Walton showed good handling to keep hold of Taylor's shot from range, as the visitors went into the interval with only one goal to show for their efforts.
Whatever Tony Mowbray said at half time certainly paid dividends as Rovers grabbed an equaliser in fortuitous circumstances.
Downing's corner was nodded goalwards by Johnson, and although Anfernee Dijksteel was in the right place to nod off the line, it cannoned against Phillips before finding the net.
The home side's tails were up by this point, with Phillips having to be secure to hold onto Dack's curling effort from the edge of the box.
A double change saw the introduction of Danny Graham and Joe Rothwell, but it was Charlton who had the next chance, with Rovers thankful to Charlie Mulgrew for getting a touch on substitute Connor Gallagher's close range effort.
But soon after the visitors regained the advantage through Taylor, who was in the right place to flick a Jason Pearce header into the corner of the net from a couple of yards out.
Time was running out for Rovers to rescue a point on the opening day, but only a great save by Walton with his feet denied Jake Forster-Caskey from making the game safe with just five minutes remaining.
Rovers never ralied though, and ended up being flat and disappointed on the opening day of the campaign.
Rovers: Walton, Bennett, Lenihan, Mulgrew (c), Bell, Travis (Buckley, 80), Johnson, Downing (Rothwell, 69), Armstrong (Graham, 69), Dack, Gallagher.
Unused substitutes: Leutwiler, Nyambe, Brereton, Evans.
Goal: Phillips OG, 52
Charlton Athletic: Phillips, Dijksteel, Pearce (c), Sarr (Gallagher, 65), Purrington, Williams (Morgan, 80), Lapslie (Oshilaja, 90), Lockyer, Pratley, Forster-Caskey, Taylor.
Unused substitutes: Amos, Bonne, Solly, Wiredu.
Goal: Purrington, 43, Taylor, 77
Booked: Sarr, 8, Forster-Caskey, 73, Lapslie, 79
Referee: Andy Woolmer.
Attendance: 14,184 (1,077 away).