ALBION defender Shane Duffy has no regrets about swapping one Ireland for another.

Duffy represented Northern Ireland at youth level and was even picked for the senior side as an unused substitute when he was just 17.

He will line up against them for the Republic of Ireland in a friendly in Dublin on Thursday (7.45pm).

Duffy told The Argus: "It's quite difficult. My dad's from the Republic. We moved to Northern for my mum to live there.

"The way it was going with Ireland schools I couldn't go and play for the Republic unless I went to school there.

"I had to wait until I got to Everton. I was saying I'm not Northern Irish, I'm Irish. It is true, people can laugh about it, but I'm proud to be Irish.

"I'm grateful to Northern Ireland for giving me a chance, but they knew when I was quite young that I was always going to change."

Duffy is playing for tough taskmasters in Martin O'Neill and his controversial assistant Roy Keane.

Duffy said: "I know he gets some stick from the outside, but he's great, if you can't take advice from Roy Keane then who can you take it from?

"He might be hard on you, but it's just his demanding standards. He wants to make you better and the team better without really showing it.

"That's the way his mentality has been since he started playing the game. I enjoy working with him. When he speaks you've got to listen.

"It's the same with the manager, they are both experienced and have a lot of knowledge. He (Keane) can have his uproars and say what he wants, but when it comes to football and the changing room it's quite different."

Duffy is as important at the heart of the defence for his country as he is for Albion in a period of transition for the Republic under O'Neill, who won 64 Northern Ireland caps and skippered them at the 1982 World Cup finals.

They reached the last 16 of the 2016 Euros in France but were thumped by Denmark in the qualifying play-offs for the World Cup finals in Russia this summer.

Stalwart defender John O'Shea retired in June after 118 caps and they have struggled in the UEFA Nations League, losing home and away to Wales.

They visit the Danes on Monday (7.45) after drawing against them at home last month.

Duffy said: "It's going to be tough, gelling and getting the right team again. There are a lot of new players with not many caps. Two years down the line, when the Euros are here, they'll have played a lot more.

"We'll see, you've just got to be patient. It's hard because it's your country and it's not nice, but we've still got a good squad with good players.

"If we get it together I think we've got a real threat. We've just got to back the manager, back the lads.

"We might be short of a little bit of talent, but we've always got the heart and desire to go and try to win the game."