Rory Patterson settled a pulsating clash with an 86th-minute winner to sink Drogheda 3-2 and boost Derry City's Airtricity League Premier Division title challenge at Hunky Dorys Park.

The Boynesiders dominated the first half, but fell behind on 39 minutes when Alan Byrne turned a Barry McNamee corner into his own net, and worse was to follow for the hosts just past the hour mark when Patterson pounced on a bad mistake by Philip Hand.

Substitute Declan O’Brien looked to have rescued a point for the Boynesiders with two goals in a minute, but Patterson had other ideas and produced a classy strike to snatch it for the Candystripes four minutes from time.

Drogheda made the more encouraging start and with more composure either Gary O’Neill or Ryan Brennan could have given them a sixth-minute lead, before David Cassidy’s spectacular volley dipped over Derry 'keeper Gerard Doherty’s crossbar.

But the best chance of the opening quarter fell to the visitors on 22 minutes when Patterson beat the offside trap to latch onto a Barry McNamee pass before driving a diagonal shot narrowly wide.

Over the next five minutes, though, two even better opportunities presented themselves to Drogheda as Byrne rifled wide from close range and then Cathal Brady also missed the target with the goal gaping.

Not for the first time this season the home side were made to pay for their poor finishing on 39 minutes when, from the third in a series of Derry corners, McNamee’s kick was turned into his own net by Byrne.

The Boynesiders almost levelled from another corner as Byrne’s header was nodded off the line by Barry Molloy and Cassidy’s follow-up shot was blocked by teammate Ryan Brennan in the six-yard area.

But right on half-time Micheal Schlingermann in the Drogheda goal had to go full-length to his left to push Patterson’s piledriver round the post.

In a storming start to the second half, Doherty made a stunning reaction save from O’Neill inside 20 seconds, before Derry replied with efforts from McNamee, Deery and Patterson in quick succession.

But the Louth side were pressing hard for an equaliser when disaster struck on 62 minutes as Hand’s suicidal pass in midfield gifted an opening to Patterson and he duly rolled the ball past Schlingermann.

For a spell it seemed that the Candystripes would canter to victory, but on 77 minutes Drogs sub O’Brien diverted Gavin Brennan’s corner to the net and barely a minute later ‘Fabio’ blasted home to make it 2-2.

But Drogheda’s porous defence came back to haunt them and Schlingermann was left badly exposed in the 86th minute when Patterson was put through and he found the top corner with a classy strike.

Drogheda United: Micheal Schlingermann; Brian Gannon (Shane Grimes 33), Alan Byrne, Derek Prendergast, Philip Hand; Cathal Brady (Declan O’Brien 52), David Cassidy (Eric Foley 67), Paul O’Conor, Ryan Brennan, Gavin Brennan; Gary O’Neill.

Subs not used: Alan McNally, Graham Rusk, Michael Daly, Gabriel Sava.

Derry City: Gerard Doherty; Simon Madden, Shane McEleney, Ryan McBride, Sean Houston (Ryan Curran 90); Kevin Deery (Michael Duffy 72), Ruaidhri Higgins, Barry Molloy, Barry McNamee; Mark Griffin (Stewart Greacen 90 +2), Rory Patterson.

Subs not used: Tony McNamee, Conall Kelly, James Gallagher.

Referee: Alan Kelly (Cork).