First-half goals from Ronan Finn and Dave McAllister ensured a badly-needed win for Stephen Bradley’s side, while driving another dagger in the champions’ hopes of replicating Rovers’ four-in-a-row achievements from the 1980s.
They now lie a massive 15 points behind runaway leaders Cork City with any hope of a turnaround looking highly unlikely as Stephen Kenny’s side appear a shadow of the team that made such an impression in Europe last season.
Coming into the game on the back of the previous week’s 2-1 defeat away to Galway Utd, the Louth men looked shorn of confidence early on.
Rovers seized on this by pressing high and forcing errors. Their drive from midfield was not matched, with Gary Shaw leading the line superbly well against an untested centre back combination of Sean Hoare and Paddy Barrett.
The home side were on top from the off with McAllister rippling the side-netting with a stunning volley on 11 minutes that half the ground thought was in. Dundalk’s only real attempt of note came three minutes later when a Michael Duffy free was tipped over by Tomer Chencinski.
The visitors looked shaky at the back and were eventually punished on 17 minutes when Simon Madden tore up the right to pull back for former Dundalk midfielder Finn, who slotted past Gary Rogers with the outside of his right boot to make it 1-0.
Conor Clifford did go close to an equaliser soon after with a long range drive that skimmed the roof of the net but it was largely Rovers who looked threatening and they deservedly doubled their lead on 37 minutes.
Graham Burke’s corner picked out the unmarked McAllister, who headed home from close range to leave Rovers in dreamland at the break.
It could have got worse for the champions seven minutes after the restart but for a wonderful save from Rogers to keep out Gary Shaw’s bicycle kick attempt.
Dundalk did have strong penalty appeals turned away on 56 minutes when Dane Massey’s cross appeared to come off the arm of Roberto Lopes under little pressure but referee Rob Rogers was uninterested.
They did manage a consolation in the 94th minute. Just after Darren Meenan picked up a second yellow card for a dive, Patrick McEleney’s free was floated over Chencinski by the head of Niclas Vemmelund.
It was too little, too late though. In truth, Rovers couldn’t have been more comfortable in claiming a first league win over Dundalk in 12 attempts, dating back almost exactly four years to May 6th 2013.
Back in October 2015 Tallaght was the ground where Dundalk won their second league title under Kenny. Fast forward 19 months and it appears the Dublin 24 venue is where their hopes of a fourth were all but ended.
Chencinski; Madden, Lopes, Webster, Byrne; Meenan, McAllister (Bone 90), Finn, Clarke; Burke (Miele 80); Shaw (Boyd 80).
Rogers; Vemmelund, Barrett, Hoare, Massey; Clifford (Kilduff 71), O’Donnell (Shields 32); Mountney, McEleney, Duffy; McMillan (Stewart 81).
Rob Rogers (Dublin).