EVER the perfectionist, Matt O’Riley couldn’t help but feel a little deflated after earning his first cap for Denmark during the week.

O’Riley was substituted in the 60th minute of the game, and his country went on to lose 2-0 to Northern Ireland, making the occasion something of a bittersweet one for the Celtic midfielder. As it did his birthday, though his new teammates marked the occasion of him turning 23 that evening in any case.

He didn’t get to such a stage in his career by not being hard on himself, but even still, it took an older head around the Danish dressing room just to give O’Riley a little bit of perspective, and to give him a fairer assessment of his contribution on his debut appearance.

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And also, to give him a little bit of a red neck, as he was rather press-ganged into addressing a room full of his colleagues after they had serenaded him at length by singing the Danish version of ‘Happy Birthday’.

"Initially, straight after the game, I didn't think I played well,” O’Riley said.

“I played for 60 minutes and we lost the game, the emotions are high and you think you didn't play well.

“On further reflection and having spoken to people, I was probably too hard on myself as I've had some pretty good feedback from most people who watched the game, which is nice. At the same time, I have high standards and I always think I can do better.

“I got really nice feedback from Kasper Schmeichel. As a debutant, he stood up and spoke about me after the game and said some really nice words about my time in the camp.

“He said he felt I did well in the game and it meant a lot. That was before I had to speak in front of the whole room myself, which was quite nerve-racking. But Kasper was really nice towards me, as most people there were. They all made me feel so welcome which made it easy to settle in.

“It made it extra nice that Kasper said it in front of everyone too. After the game I felt quite disappointed because of the outcome. But I was maybe being quite hard on myself, as I can be in moments like that. I tend to be a bit more emotional than logical.

“But Kasper has been around for such a long time and it was nice to get the positive feedback.”

While the marking of O’Riley’s birthday was also appreciated, the manner of it was perhaps less welcome.

“It was right after the game,” he said.

“It was a weird night. I’d to speak in front of the room after Kasper spoke then eight minutes later it was my birthday.

“The whole room sang happy birthday in Danish which I didn’t realise was four times as long as the English version.

“So, I just kind of stood there for a long time and then everybody sat down. Then I’d to speak again to say thanks again in Danish.

“I didn’t prepare anything as I didn’t know it was happening. It just happened in the moment, so I just spoke from the heart about how I felt at the time.

“They are really good at that – making you feel welcome and part of it. Obviously most of the people who were there probably didn’t know me from a young age as I’ve grown up in England, come through English academies and was better known in England than in Denmark.

“It’s nice to feel part of it now as I’m getting older and more established.”

One of the more entertaining aspects of O’Riley’s week on international duty for those on the outside has been the contributions of his grandma, Lis, who is responsible for his Danish eligibility.

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Not only did the 85-year-old come out swinging at those who doubt his passion for his country having been brought up in England, but she also revealed the rather fanatical obsession with Celtic she has picked up since her grandson made the switch from MK Dons.

"She is pretty full on,” O’Riley said.

“She watches every game as well as the Celtic podcasts. She probably knows more about football than a lot of people, to be fair to her.

"She's watched me since I was about eight years old at Fulham and before she moved back to Denmark. She's been around the football environment for a long time.

“It's good that she's able to access all of the games on television back in Denmark so she really enjoys that aspect of being able to watch her grandson on a regular basis.

"I've been really lucky with my support system from a really young age in terms of my mum and dad especially. They would drive me all over the place to every game. They have really been there for me and are still coming to all of my games.

"That's something I have been really lucky with. I don't take that for granted either but it is definitely allowing me to go on the pitch and play a lot more relaxed. There is less pressure on myself as they just tell me to go out there and have fun.

“My grandma in Denmark has been a big part of that too.”