Eric Kinder's young side scored two second half goals as they began the new season as they ended the last with victory on their travels.
Jordan Preston fired Rovers in front on 48 minutes before their dominance was confirmed as Modou Cham marked his first start at u21 level with his first goal to secure the points 12 minutes from time.
Injury and illness meant Rovers were without Hyuga Tanner, Jordan Slew, Connor Mahoney and Devarn Green, but they didn't let affect them with an impressive performance at Culver Road.
The tone was set from the off with Preston firing just wide inside the first ten minutes, before Cham went close after neat approach play.
John O'Sullivan was next to chance his arm after a trademark run, forcing a fine save from Seagulls' keeper Joshua Smith.
A minute later Smith was Brighton's saviour once more as he tipped a Preston shot onto the post before a quick break saw Modou Cham denied.
Rovers continued to press but couldn't find the goal their first half play deserved, Darragh Lenihan twice going close in the latter stages.
Thankfully Rovers weren't to regret those missed chances in the first half as they scored almost immediately from the restart.
On 48 minutes good play down the right saw Dean Rittenberg get around the Brighton back line before crossing it to the back post to where Jordan Preston headed home the opening goal.
The lead was almost doubled moments later when O'Sullivan crossed for Rittenberg but he put his effort just wide of target.
The home side had a rare sight of goal on 70 minutes when Robin Deen fired wide, before Will Collar headed over.
But any thoughts of an Albion comeback were put firmly to rest when Rovers grabbed a deserved second 12 minutes from time.
The goal was made by the lively O'Sullivan who raced to the byline before pulling the ball back for Modou Cham to score his first goal for the development squad, crashing his close-range effort in off the crossbar.
Rovers perhaps should have had further goals as Preston was denied a second, but Kinder's young side saw out the remaining minutes with composure to register their first three points of the season.
BRIGHTON: Smith, Barry, Hunt, Asmundsson (sub Collar 20 mins), Dallison, Barclay, Deen (sub Tighe 84 mins), Hutchinson, Muitt, Wiltshire (sub Cole 59 mins), Starkey.
Subs not used: Doherty, White.
ROVERS: Raya, Daly, Lavelle, Lenihan (c), Doyle, Rittenberg (sub Joel 75 mins), Carson, Bauress, Cham, O'Sullivan, Preston.
Subs not used: Paulo Jorge, Crump, Pierce.
Goals: Preston 48, Cham 78.