Bray notched up another scalp in Oriel Park with an unforeseen victory over the champions.
A scoreless first half was followed by an explosion of goals just before the hour, Gary McCabe putting the visitors ahead from the spot only to be negatived within minutes by Stephen O'Donnell.
A second penalty barely ten minutes later also converted by McCabe was followed by an intervention by Ryan Brennan to put the Seagulls a further goal ahead.
And the visitors held out through to the end of time added.
The hosts were aggrieved by what seemed to them unjustified penalties awarded against them, but long before that they had failed to take advantage of the openings they created.
As early as the ninth minute, Conor Clifford met Michael Duffy's flag-kick but shot straight at Peter Cherrie.
A flurry of Dundalk activity about the quarter hour mark saw Gary Rogers tempt Cherrie forward for a long-range free that almost deceived the Bray keeper, and a crossfield ball from Chris Shields a minute later found Jamie McGrath, who turned and shot, but the Scot claimed well.
Bray's play for the time being was largely concerned with damage limitation, and cost them four bookings before the break.
What was perhaps Dundalk's best opportunity came just before the half hour, when a nice piece of skill from Pat McEleney saw him send the ball through, following round Tim Clancy to curl a threatening shot just over the bar.
Then on the counter, Clancy beat Brian Gartland in the air to a corner and headed goalwards, Niclas Vemmelund doing well to clear off the line with Rogers stranded.
The home side put a strong effort into their attack as the interval loomed, but the game stayed stubbornly goalless.
The second period had seen an early effort by Duffy before the referee deemed O'Donnell's push on Aaron Greene worthy of a spot kick, to the dismay of the home faithful. Rogers guessed right, but couldn't stop McCabe's shot.
The Lilywhites struck back almost immediately, however, O'Donnell chipping the Bray netminder following a neat pass by David McMillan.
But the Seagulls were handed an advantage when Brennan went down in the aftermath of a Bray free, and Referee McKell again pointed to the spot. McCabe stepped up again, and again beat Rogers to the right.
With the visitors once more in the driving seat, Dundalk's probing took on a more desperate tone, and also left gaps at the back, but when a Connolly cross was cut out by Vemmelund it seemed a lost chance until Brennan intervened, slamming the rebound past former Seagull Rogers to give them a two-goal cushion.
It was enough to see the points travel back to Wicklow, and a fitting if somewhat delayed riposte to the 8-1 humiliation handed out by the hosts at the same venue almost two years ago.
Compiled by Mícheál Ó hUanacháin