Patrick Hoban's 94th-minute penalty secured Dundalk a dramatic victory over ten-man Bohemians at Oriel Park.
A thrilling game looked set to end in a 1-1 draw but, with the game in the fourth minute of stoppage time, substitute Dean Jarvis was upended in the box by Andy Lyons and Hoban beat James Talbot for the third time this season to keep Dundalk top of the league.
Bohs pulled ahead with less than two minutes played when Robbie McCourt's pass caught the Dundalk back four square and even though he was stood up by Gary Rogers, Danny Grant still managed to find the net from an acute angle.
It was one-way traffic after that and Dundalk should have leveled things in the 17th minute but Michael Duffy sliced his effort horribly wide and Bohs could have gone in two ahead at the break when Ryan Swan hustled Sean Gannon into a mistake outside his penalty area but the Bohs striker couldn't apply a clinical finish.
Bohs substitute Ryan Graydon lasted a total of 13 minutes before he received his marching orders from Derek Tomney.
Booked just seconds after the restart, the 20 year-old left his team to play 36 minutes with ten-men for a silly tackle on Daniel Cleary which led to his departure.
Dundalk went for the jugular with coach Vinny Perth dispatching Georgie Kelly to play alongside Hoban in the front line and the move paid off in the 66th minute when the striker buried a loose ball past Talbot to make it 1-1.
Talbot made a brilliant save to deny Hoban with four minutes to go and Bohs thought they snatched it when Danny Mandroiu jinked his way to the byline but Robbie McCourt couldn't sweep his cutback home.
Play switched to the other end and when referee Tomney blew for the spot-kick, Hoban made no mistake with his sixth penalty of the season.
DUNDALK: Gary Rogers; Sean Gannon, Daniel Cleary, Sean Hoare, Dane Massey (Dean Jarvis 84); Chris Shields, Jordan Flores (Sean Murray 64); Daniel Kelly (Georgie Kelly 56), Patrick McEleney, Michael Duffy; Patrick Hoban
BOHEMIANS: James Talbot; Andy Lyons, James Finnerty, Aaron Barry, Darragh Leahy; Robbie McCourt, Conor Levingston; Danny Grant (Ryan Graydon 40), Danny Mandroiu, Luke Wade Slater; Ryan Swan (Ali Reghba 68) (Scott Allerdice 80)
REFEREE: Derek Tomney