Reggina defeated Atalanta for their first victory in 2009 to revive their hopes of avoiding relegation.
Amaranto striker Fabio Ceravolo scored the only goal of the game after 40 minutes to seal a win that takes them to within four points of safety with six games remaining.
Nevio Orlandi's men could have won by a a bigger margin but were denied by the woodwork on three occasions.
The visitors went into the game in desperate need of points with their winless run stretching back to November 23, when they beat Atalanta 3-1.
Since then, Orlandi's side, who are at the foot of the standings, had only managed to collect nine points out of a possible 54.
The victory will be a big boost in confidence for Reggina, who meet Scudetto contenders Juventus next weekend.
Luigi Del Neri's Atalanta were determined to end their three-game winless run.
They created the first chance of the game in the eighth minute, with Cristiano Doni's free-kick going high over the bar.
Tiberio Guarante came closest shortly after, with his free-kick towards the near post forcing Reggina goalkeeper Christian Puggioni into a full-length clearance.
The hosts put a great move together in the 15th minute, with Doni playing a one-two with Sergio Floccari before firing a right-footed strike from the edge of the area that went inches wide of the far post.
Midway through the first half, Puggioni made two good saves to keep out Guarante and Luca Cigarini's powerful strikes from distance.
The visitors had their first shot on goal five minutes before the break and it was sufficient to break the deadlock.
Atalanta goalkeeper Andrea Consigli parried away Andrea Costa's strike but only as far as Ceravolo, who fired in a left-footed effort from close range to put his team in front.
Reggina defended deeply to go into the break with a narrow advantage.
Atalanta should have levelled the scores early in the second half but Puggioni made a fine save to keep out Floccari's powerful header.
At the other end, Edgar Barretto's stinging drive from distance beat Consigli but rebounded off the near post.
The Bergamaschi missed a golden chance to equalise on the hour mark with Simone Padoin's effort from inside the box cleared by Puggioni but only as far as Floccari, who fired wide, much to the anger of the home fans.
Reggina opted to defend deeply and hit their rivals on the counter-attack.
They almost succeeded in putting the game beyond their rival's reach in the 85th minute but Franco Brienza's lobbed effort beat Consigli but rebounded off the crossbar.
Substitute Marino Defendi almost equalised two minutes from time but his right-footed volley from the edge of the area was met by a crucial save from Puggioni.
Reggina could not believe their luck as they were again denied by the woodwork.
Brienza's through ball found substitute Francesco Cozza, whose right-footed effort from the edge of the area beat Consigli but struck the far post.