The striker has had to wait patiently for his moment, and it finally came eight games into his City career, but he then runed it with a needless foul which saw him red-carded.
That moment changed the momentum of the game back in favour of Drogheda, who responded with two goals in five minutes from former Ballymena United defender Conor Keeley before Warren Davis sealed the win late on.
It is now four defeats and four red cards in nine games for Tiernan Lynch, who watched his team pass up a huge opportunity to close the gap on the leaders to just one point.
Over 30 minutes had passed by the time either side created a chance and inevitably Michael Duffy was involved. Adam O’Reilly left Ryan Brennan for dead on the touchline before latching onto a return pass from Ronan Boyce in the penalty area.
The midfielder lofted a cross into the six-yard box where Liam Boyce controlled it before laying it off for Duffy, whose snapshot was straight at Luke Dennison.
Drogheda responded with a rare chance of their own, this one coming from a set-play as Shane Farrell’s corner found Thomas Oluwa free at the back post, but he headed wide.
The game finally sparked into life just after the hour mark with a goal which was desperately needed. It came from brilliant work from Ronan Boyce on the edge of the penalty area, as he dug out a cross into the area where Liam Boyce pounced, guiding a header over Dennison and into the net for his first goal in a Derry shirt.
But celebration turned to despair for Boyce and Derry within minutes. Just 60 seconds after scoring, Boyce was red -carded, needlessly fouling Keeley to pick up his second yellow card. It was the Candystripes’ fourth red card of the season in just their ninth game.
Boyce had barely left the pitch when Drogheda equalised. The home side were still organising themselves into playing the remainder with 10 men when Shane Farrell’s cross from the right was met by Keeley, who volleyed in past Brian Maher from 10 yards.
An incredible period in the game then took another twist as Drogheda took the lead just seven minutes after falling behind, Connolly’s header coming straight to Keeley who volleyed in his second spectacularly to silence the Brandywell.
Drogheda sealed the points just four minutes from time when Owen Lambe’s throw in was flicked backwards into his own area by Kevin Holt and Warren Davis was there to score from close range.
Derry City: Maher, Boyce, Cann (Ferguson 75), Connolly, Holt; Winchester, Benson (Whyte 75), O’Reilly, Mullen (Patton 82), Boyce, Duffy.
Drogheda United: Dennison, Kane, Quinn, Markey, Oluwa, Farrell (Heaney 72), Bolger, Brennan (Boyle 82), Keely, Lambe, Davis.
Referee: Rob Harvey (Dublin).
Man of the match: Conor Keeley
Match rating: 5/10