Declan O’Brien’s spot kick separated the sides at Hunky Dorys Park as Drogheda United hung on for all three points with a 1-0 win against a spirited Bohemians side.
The Boynesiders’ leading scorer struck after 36 minutes following a foul on Gavin Brennan, and Peter Hynes should have doubled their lead soon after.
But Bohs had a Dinny Corcoran effort ruled out on the stroke of half-time and were the better side in the second half, with Evan McMillan foiled twice by keeper Gabriel Sava before Dwayne Wilson had a shot scrambled off the line in stoppage time.
The visitors were furious at the refereeing of Rob Rogers and manager Aaron Callaghan and some of his players surrounded the official on the pitch after the final whistle.
This game was slow to come to life, with two wayward efforts from Bohs’ Kevin Feely and Keith Ward and a comfortable save by their keeper Andy McNulty from a deflected Sean Brennan free kick the high points of a disappointing opening 35 minutes.
But then Gavin Brennan dispossessed Ward in the Bohs penalty area and was then taken down by Roberto Lopes, and Declan O’Brien comprehensively beat McNulty from the penalty spot.
And on 39 minutes Peter Hynes missed a chance to double Drogheda’s lead, nodding over the bar from close range after Gavin Brennan had supplied the cross.
But on the stroke of half-time Bohemians felt hard done by when Dinny Corcoran tapped in from close range, only for Mr Rogers to penalise Adam Martin for an innocuous aerial challenge on keeper Gabriel Sava who spilled the ball.
The visitors had the first openings of the second half - a Ryan McEvoy shot which was deflected narrowly wide by Derek Prendergast and a Karl Moore effort which was well held by Sava.
Prendergast countered with a poor header from a Sean Brennan corner, but Bohs kept pressing for an equaliser and Sava was called upon to save from an Evan McMillan header before Dwayne Wilson had a shot scrambled off the line deep into stoppage time, with Bohs claiming for a hand-ball in the box.
Drogheda United: Gabriel Sava; Stephen Quigley, Derek Prendergast, Alan Byrne, Philip Hand (Briam Gannon 61); Sean Brennan (Ryan Brennan 71), Paul Crowley, Eric Foley, Gavin Brennan; Peter Hynes (John Sullivan 81), Declan O’Brien.
Bohemians: Andy McNulty; Owen Heary, Evan McMillan, Kevin Feely (Michael Barker 31), Roberto Lopes; Karl Moore, Ryan McEvoy, Keith Ward, Adam Martin (Stephen Traynor 74), Dwayne Wilson; Dinny Corcoran (Andy Mulligan 65).
Referee: Rob Rogers (Dublin).