Forest needed to get their play off bid back on track after losing to Reading on Friday, and did so with three hard-earned points.
Things didn't look good when the influential Gareth Williams was taken off after just eight minutes with what looked like to be a dislocated shoulder and things almost got even worse when Burnley's Richard Chaplow should have scored.
He only had Darren Ward to beat but he shot wide, and the visitors again came close on 20 minutes when Ward came for and missed a cross and Ian Moore's header hit the crossbar.
Forest's best first-half chance came on 22 minutes when Marlon Harewood crossed for David Johnson whose header beat Nik Michopoulos in the Burnley goal but drifted agonisingly wide.
The second half started with the visitors growing in confidence as nerves started to strike at the heart of the young Forest team.
Andy Reid could have calmed the nerves of his team-mates and the 25403 crowd when he raced through on goal, but missed the target.
With desperation beginning to creep in Michael Dawson joined his forwards and it was his thunderous 75th minute 30-yard drive that finally put Forest in front.
Minutes later Lester himself could have wrapped up the game and the points but his shot went inches wide and we had to wait until the 90th minute for the points to be sealed in this tense game.
Eugen Bopp headed a long ball into the path of Johnson, who finally put everyone out of their misery, slotting home when left one-on-one with the keeper.