The Tigers took the lead with 10 minutes remaining in the first-half as Robert Koren converted a penalty awarded against Simon Gillett.
Simon Cox's absence saw Billy Sharp named as a lone striker, supported by James Coppinger and it was Sharp who snapped up the second spot-kick of the game as he levelled the scores just before the break.
Penalties looked to be the only way through for either side but it was a defender, Paul McShane, who made the second-half breakthrough when he headed in Koren's cross.
Lewis McGugan and Dexter Blackstock entered the fray in a bid to save a point for the Reds, who produced a late flurry, but the majority of the 19,472 crowd went home disappointed.
Full match report to follow on Forest Mad.