Republic of Ireland boss Stephen Kenny is urging Adam Idah’s critics to lay off the youngster.

The Norwich City striker has been ruled out of Wednesday’s final Nations League tie against Bulgaria through an unspecified injury, according to the Football Association of Ireland’s official twitter feed on Monday afternoon.

That leaves him a doubt for the Championship resumption at Middlesbrough, although Daniel Farke will provide a full fitness update on his squad later in the week.

Idah had started again in the Republic’s 1-0 Nations League loss to Wales on Sunday, after being fast-tracked into new Irish coach Kenny’s senior plans, but is yet to score in five appearances for his country. That included a high profile date at Wembley last week in a 3-0 friendly defeat to England.

The 19-year-old was a stand out performer for Kenny at under-21 level, and is earmarked as a bright future prospect following the international retirement of Sheffield United forward David McGoldrick.

“He isn’t the finished article, nor would we claim he is, but he is someone with real potential,” said Kenny after his side’s latest setback in Cardiff. “One of the things we have done is given players an opportunity with the World Cup qualifiers in mind. Adam Idah, I know he’s not scoring, is showing he is a different type of striker than we have had recently.”

Television pundit Roy Keane was scathing in his assessment of the toothless Irish after the latest defeat in Wales. The Republic legend believes rookie boss Kenny is already under pressure, after failing to win any of his first seven games.

“At the end of the day, we haven’t won and I know that, I realise that,” said Kenny, quoted in the Irish Sun. “Wales are quite a strong team, you’re not going to come over and create loads of chances against them away from home.

“We knew we had a tough game coming here.

“Gareth Bale, David Brooks and Daniel James are a good front three and they have a good team, Wales. It’s been well documented many players are missing so it was a challenge for us to rise to the occasion and I felt the players showed a level of intensity, a real high work ethic and good teamwork but unfortunately we’ve lost.”

Idah has had a mixed start to his club season. He notched the winner on the opening day at Huddersfield Town but conceded a penalty at Rotherham and was banned for three games for a late red card against Wycombe.