Stephen Kenny said he did not want another gallant defeat. This historic ignominy was not what he had in mind. Gerson Rodrigues’s fierce long-range goal five minutes from time earned Luxembourg a famous win that leaves Ireland’s World Cup qualification ambitions hanging by the skimpiest of threads and Kenny under heavy pressure. His record as manager reads: played 10, won 0.

Kenny has been unlucky, never able to field a full-strength side, but Luxembourg, ranked 98th in the world, are the lowest-calibre opponents he has faced and were supposed to be the side against whom he oversaw his first win. Instead Ireland flopped to a new low, with defeat the consequence of a grim performance. Meagre skill, not much zest. Whereas there were positives amid Wednesday’s loss in Serbia, this was an unvarnished flop.

“It was a horrible night, an embarrassing night,” said captain Séamus Coleman. “It looked like we didn’t have belief in ourselves. We didn’t demand the ball as much as we should have and look to break them down. We got what we deserved, which was nothing.”

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Coleman did not seek to shift responsibility on to the manager.

“As players we’ve got to weather the storm now. We’re going to get criticism and it will be deserved criticism. I’ve never hidden behind managers at club level and I don’t do it at international level. As players we should have had enough on the pitch to get a result. We needed to show some character and we didn’t do that.”

Kenny was aghast by his team’s display, saying: “It’s not acceptable to lose in the manner that we did.” Asked whether he feared for his job, he replied that he did not. “We all have setbacks at times but I have absolute conviction that I can do a good job here. Tonight doesn’t back that up, I realise that. We have to accept that criticism and fight harder, do better.”

The most alarming thing for Ireland was that Luxembourg’s goal did not come as a shock. The visitors, who arrived on the back of losing to Qatar on Wednesday, had looked comfortable for most of the match and created more chances in a game of few.

Kenny had called for a fast start by his team but the visitors threatened in the second minute, as a curling shot from the edge of the area by Vincent Thill drew a smart save from Gavin Bazunu, the 19-year-old goalkeeper whose form this season for Rochdale, where he is on loan from Manchester City, persuaded Kenny to give him a senior international debut. Bazunu’s performance was the only bright note on a bleak night for Ireland, although they would have preferred him to have been less busy.

Kenny had also stressed the need for zippy passing to unhinge Luxembourg but his team were ponderous. They never found rhythm in the face of energetic pressing.

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Not until the 18th minute did Ireland muster a shot and it came from the sort of intricate move that Kenny advocates. Bazunu started it at the back and Collins nearly finished it at the other end, sliding in to meet a cross from the left by Callum Robison. Goalkeeper Anthony Moris made a fine save. The beginning of an onslaught? Far from it. Ireland did not work another opening in the half and almost suffered a shock just before the break when Rodrigues sent a lob towards goal from over 20 yards. Bazunu backpedalled swiftly to avoid being beaten in the same way that Travers was against Serbia.

Robbie Brady, a half-time substitute, brought a glimmer of ingenuity to Ireland’s forward play but still they seldom looked capable of penetrating. Bazunu had to make another save to foil Vincent Thill as Luxembourg grew in confidence. Rodrigues gave them victory when he rammed an excellent low drive beyond the helpless Bazunu from 25 yards.