Stephen Kenny's side missed their chance to take one step into the round of 32 with defeat to Dutch side AZ Alkmaar
Dundalk squandered their opportunity to take one step into the Europa League round of 32 with a disappointing 1-0 defeat to AZ Alkmaar at Tallaght Stadium.
Stephen Kenny's side were left frustrated for large periods of the game and struggled to find any rhythm, their usually energetic and accurate play missing from this evening's game.
Netherlands U21 international Wout Weghorst needed just nine minutes to score the game's winning goal after pouncing on a loose ball in the Dundalk area.
Dundalk got off to an uncharacteristically sluggish start this evening in Tallaght. The complaints going into many of their European ties was that the workload had been too much and fixture congestion had taken its toll.
Their 2-1 defeat to Zenit at home before the end of the domestic season saw them play their 5th game in 12 days. With their last game coming against Cork City in the FAI Cup final at the start of the month, it was difficult to understand the slow start.
Perhaps Zenit's 2-0 victory over Maccabi Tel-Aviv played a role in it, the Russian side victorious meaning that Stephen Kenny's men needed as little as two draws in their final two games to progress.
But the opening five minutes saw a litany of misplaced passes and none of Dundalk's usual suspects looked on song.
Gary Rogers was forced into action early to punch clear a cross but the breakthrough came after just nine minutes. An AZ corner was cleared from inside the area - a high speculative cross it must be said - but took an unfortunate flick off the thigh of Dane Massey.
Wout Weghorst was alive to the situation and finished neatly to put the visitors ahead.
The goal should really have shook the Premier Division champions into action, but it took longer again to see their first clear cut chance of the game.
Stephen O'Donnell, usually so reliable in Europe for Dundalk, played a stray pass which ultimately led to nothing but was another stark reminder that even under no pressure, Kenny's men were miles off the pace.
O'Donnell would last only 42 minutes and was withdrawn with injury shortly before the half with what appeared to be a muscle injury.
By then, Dundalk had come alive. Daryl Horgan, Robbie Benson and Ciaran Kilduff linking up with a few neat passes, but that was perhaps the best passage of play in the opening 45 for the home side.
Alireza Jahanbakhsh gave Massey trouble for large periods of the game this evening and continued into the second period, when AZ completely knocked the wind out of the Dundalk sails.
The second half, which promised so much considering the courage we'd seen in Dundalk in recent months, lacked any sort of urgency.
Three superb Rogers saves in the second half was enough to keep the game alive going into the final quarter, but the Irish side found little in the way of chances.
Not until the final 10 minutes did they have any real attempts on goal and the introduction of David McMillan in the second half did little to inspire the subdued home crowd.
Dundalk slip out of the qualification places with defeat tonight, one point behind AZ who move up on five points. They'll need a victory against Tel-Aviv later this month, but with AZ now in the driving seat, Stephen Kenny's side will have a lot to do to qualify for the next round.