The cup holders staged a brave late rally in an effort to hold on to their prized silverware but the best efforts fell short of forcing a replay at the Brandywell, something the Candystripes’ second-half performance deserved.
Derry had claims for a penalty turned down as the game entered stoppage time after Rory Patterson raced in on goal following a superb interception by substitute Michael Duffy at the other end.
Sligo were on top during the opening 45 minutes as the visitors offered little to trouble their hosts up front.
Derry came under pressure in the opening three minutes as the home side put a few passes together, but the Candystripes back line dealt with the early threat by Sligo.
Rory Patterson took the ball off the toe of a Sligo defender after five minutes but the Derry striker was unable to make the move count.
Sligo went ahead on 15 minutes when a Joseph Ndo free-kick fell nicely for Cretaro, who found Gerard Doherty’s net.
Solid Derry defending by Patrick Kavanagh on the half-hour kept the score to the minimum as Seamus Conneely bore down on goal. Simon Madden’s swirling effort from a clever crossfield ball by Barry Molloy then had Sligo keeper Gary Rogers struggling.
The hard-working Kavanagh, who injured himself as he attempted to keep Danny North at bay, was forced to leave the action on 39 minutes.
North went close to doubling the Sligo advantage as the half entered stoppage time, but the ball was scrambled away at the last second.
However, Declan Devine’s side came out for the second half with a lot more spirit, while the introduction of second-half substitutes Michael Duffy, Ryan Curran and Michael Rafter added more flair up front.
Cretaro had a chance to notch his side’s second after a minute of the second half, but his effort flew narrowly wide of Doherty’s goal.
Barry McNamee had a great opportunity to square the match in the 49th minute but he was unable to get a clean shot at goal.
A quick break by Sligo in the 57th minute set Aaron Greene up for a shot but he ballooned the ball over the bar.
lThe teams walked out onto the pitch holding white T-shirts as a mark of solidarity with Drogheda United striker Gary O’Neill, who has been diagnosed with testicular cancer.
SLIGO ROVERS: Rogers, Keane, Henderson, Peers, Davoren, Cawley, Ndo, Conneely (Ventre 66), Greene, Cretaro (Millien 74), North (Elding 81).
DERRY CITY: Doherty, Molloy, McEleney, Higgins, Patterson, McBride, Kavanagh (Duffy 39), Madden, Osborne (Curran 76), McDaid (Rafter 73), McNamee.
Referee: Neil Doyle (Dublin).