They managed it courtesy of a simple Hermann Hreidarsson header after 33 minutes from a Paolo Di Canio corner. From then on, Rovers lacked both the creativity and unpredictability to break down Alan Curbishley's well-drilled defence.
The Addicks boss was understandably delighted with the way his team snatched three points from a previously difficult place for Premiership sides to carve out a result.
"We deserved the victory tonight," he beamed."
Blackburn found it very hard to break us down and this was a fantastic result for us."
Blackburn forced Charlton keeper Dean Kiely into just two meaningful saves; the first a low drive from distance by Steven Reid that came through a jungle of legs and the second a looping Barry Ferguson header that Kiely turned aside.
In truth, though Rovers never really looked like scoring despite dominating much of the play. It is now five defeats in seven matches for Graeme Souness' side who are in desperate need of a pick-me-up to lift their sagging confidence.
An angry Souness said afterwards: "We had most of the possession and did enough to get something from this game. We made another mistake and it cost us again."