Fresh from their Europa League heroics on Thursday, Stephen Kenny’s side looked on course for the Aviva Stadium when Dean Shiels’ 21st minute opener against his father Kenny’s side was added to by Ciaran Kilduff’s second of the week in first half stoppage time.
However, Derry were thrown a lifeline when Rory Patterson pulled a goal back on 65 minutes before Curtis struck four minutes from the end to set up a replay at the Brandywell on Tuesday night.
Daryl Horgan, Chris Shields and Andy Boyle were the only survivors from the Dundalk side which beat Maccabi Tel Aviv in the Europa League at Tallaght Stadium with Stephen Kenny’s eight changes having an unsettling effect on the side in the early stages.
Derry had a big chance to take the lead after just five minutes when Patterson’s header forced Gabriel Sava to rather unconvincingly claw the ball away from the bottom right hand corner.
It was therefore somewhat against the run of play that Dundalk hit the front on 21 minutes.
Alan Keane made a great burst down the right and after a neat exchange with John Mountney, he beat Lucas Schubert before crossing for Shiels to head home.
Unfortunately for the former Rangers man, he took a heavy knock in that incident and was forced off clutching his arm after what was his second goal for the Lilywhites, following on from his strike against Crumlin Utd in the previous round.
He made way for fellow Derry man Patrick McEleney, who in his first involvement pulled a shot just wide.
The goal settled the home side down massively although Derry did have a fine chance to equalise in the 34th minute when Nathan Boyle teed Aaron McEneff up for a shot from the edge of the area that forced a fine low save from Sava.
However, Derry’s hopes of a turnaround were dealt a huge blow in the third minute of stoppage time when Dundalk fired home a second.
McEleney played a stunning ball into the path of Kilduff’s run with the striker completing a perfect week by controlling it before prodding past Doherty to leave it 2-0 at the break.
Derry almost halved that deficit within 17 seconds of the restart when Patterson was denied at point blank range by Sava but only the woodwork prevented them from falling further behind in the 50th minute with Kilduff heading against the left hand upright from another superb McEleney pass.
Stephen O’Donnell then went close for the home side when he turned a Shields cross just wide with Dundalk surviving a scare at the other end on 58 minutes when Alan Keane took a Ronan Curtis cross off the toe of Patterson as he was about to tap home.
Patterson did find the net seven minutes later though, mopping up the spillage after Sava had spilled Aaron McEneff’s low shot from the edge of the area after it deflected off Shane Grimes.
At that point, it was game on with Derry going close to an equaliser on 78 minutes when Sava palmed away a deflected effort from Barry McNamee before Paddy Barrett denied Schubert from the follow up.
The equaliser arrived on 86 minutes when Curtis controlled a free out of defence from Dean Jarvis to fire low to the bottom left hand corner.
Substitute David McMillan did have a chance to steal the win in the 94th minute but screwed over from close range after McEleney’s cross from the left found its way to him at the back post.
Sava; Keane, Barrett, Boyle, Grimes; Mountney, Shields, O’Donnell, Horgan (Benson 73); Shiels (McEleney 24), Kilduff (McMillan 82). Subs not used: Gartland, Meenan, Gannon, Rogers.
Doherty; Vemmelund, McBride (Doherty 59), Jarvis, Schubert (Daniels 81); McDermott, McCormack, McEneff, McNamee; Boyle (Curtis 52), Patterson. Subs not used: Monaghan, Ward, Castells, Patton.
G Kelly (Cork).