Derry City defenders Ryan McBride and Aaron Barry were their matchwinners against ten-man Sligo Rovers.
The centre-back partnership headed home City's goals, which cancelled out Eamon Zayed's opening strike for Sligo.
With virtually their first attack Rovers took the lead against the run of play on 26 minutes when Zayed made no mistake to fire home.
Peter Hutton's side missed a golden chance to level things on 36 minutes from the penalty spot but Patrick McEleney's spot-kick was saved by Richard Brush after the striker had been brought down inside the box by Kalen Spillane. Derry's pressure finally paid off on 44 minutes when Ryan McBride came up from the back to head home McEleney's left-wing free-kick.
The home side took the lead on 54 minutes as Aaron Barry nipped in at the near post to head home McEleney's corner. On 78 minutes, Rovers were reduced to ten men after Danny Ledwith received a second caution following his challenge on Dean Jarvis.
In the closing stages both Michael Duffy and Spillane both hit the woodwork for either side.
Derry City: Doherty; Kelly, McBride, Barry, Jarvis; Lowry, Molloy, McNamee (Patterson 74); Dooley, P McEleney (Houston 83), Timlin (Duffy 63).
Sligo Rovers: Brush; Ledwith, McMillan, Spillane, Davoren; Cretaro, Cawley, O'Connor, Donelon (Keating 58); Zayed (Boylan 85), North.
Referee: D McKeon (Dublin).