Rovers' Under-23s produced a spirited performance against Notts county, but Adam Campbell's stunning first-half strike proved to be the difference between the two teams.
The Magpies forward scored the only goal of the game on 27 minutes, crashing home an unstoppable shot which went in off the underside of the crossbar.
Rovers had their chances, with trialist Faissal El Bakhtaoui twice going close and Connor Mahoney looking lively throughout, but they were unable to find a way past a resolute County rearguard.
Despite the defeat, it will have served Damien Johnson's development side well ahead of their participation in this season's inaugural EFL Trophy, where they will come up against lower league opposition Oldham, Fleetwood Town and Carlisle United.
Following the first team's 1-1 draw with Girona FC at Ewood Park yesterday, Rovers' youngsters were given a chance to shine in the final pre-season friendly ahead of next weekend's big Championship kick-off.
There was still some senior experience on show, as goalkeeper David Raya, right-back Ryan Nyambe, midfielder John O'Sullivan and wing wizard Mahoney all started.
El Bakhtaoui was given another opportunity to impress up front, with the rest of the team made up of the newly-named Under-23s.
Scott Wharton and Matty Platt formed the centre-back pairing, with Jack Doyle at left-back, Connor Thomson and Willem Tomlinson in midfield, and Lewis Mansell partnering El Bakhtaoui in attack.
And it was the French forward, who last season scored 30 goals for Dunfermline, who had the game's first effort on six minutes.
Mahoney's cross from the right eventually dropped to El Bakhtaoui on the edge of the box and his crisply-struck volley skimmed the top of the net.
Rovers remained on top for the opening quarter of the game, with another Mahoney delivering deflecting just wide of the far post and El Bakhtaoui again looking lively on the ball.
The visitors threatened the County goal again on 25 minutes when O'Sullivan's corner was headed back across goal by Platt, Wharton attempted an over-head kick and Mansell prodded the loose ball wide.
However, against the run of play, the hosts opened the scoring two minutes later. Genaro Snijders supplied a deep cross from the right, Campbell brought the ball down and smashed an unstoppable shot past Raya which went in off the underside of the bar.
Rovers looked to hit straight back and came close on 33 minutes. Mansell freed Mahoney in space down the right and after breaking to the byline, his near-post cross was almost turned into his own net by goalkeeper Adam Collin.
Aborah was pulling the strings for the home side and he saw a shot blocked, before almost setting up a second County goal on 41 minutes. After making a surging run through the centre, he slipped in Alex Rodman to his left, but Doyle got across to made a magnificent goal-saving challenge.
That proved to be Aborah's last involvement, as he limped off moments later, and the half-time whistle sounded soon after.
Just like the opening period, Rovers had the first chance of the second half, six minutes after the restart, and it came from the same source. Mahoney crossed from the right and El Bakhtaoui headed straight at Collin at the far post.
A raft of second-half substitutions disrupted the flow of the contest, with the next chance of note coming on 72 minutes, when O'Sullivan drove towards the edge of the area, before blazing over the bar.
The hosts registered an effort on target 10 minutes later when Campbell floated over a corner from the left and Hollis rose highest at the back post, but his header deflected safely into the arms of Raya.
It would prove to be the final chance of the match, as the Magpies saw the game out to secure the spoils.
NOTTS COUNTY: Collin (Loach 73), Audel, Duffy (Edwards 73), Hollis, Dickinson, Hewitt (Richards 84), Tootle (Atkinson 67), Aborah (Burke 43), Rodman (Smith 67), Campbell, Snijders (Stead 63).
Goal: Campbell (27).
ROVERS: Raya, Nyambe, Wharton, Platt, Doyle, Mahoney, Tomlinson (Travis 68), Thomson (Rankin-Costello 87), O'Sullivan, El Bakhtaoui, Mansell.
Subs: Fisher, Askew, Grayson, Magloire, Rittenberg, Howarth, Powell.
Attendance: 1,411 (135 Rovers)