AS Sunderland’s scheduled appearance at Wembley edges closer, Luke O’Nien has urged everyone connected with the club to focus on making sure the rejuvenation continues by celebrating a memorable double at the end of the campaign.

The Black Cats – who will be assessing striker Will Grigg this week after he had to withdraw from the Northern Ireland squad yesterday with an unspecified injury - are making the most of an enforced international break from League One duty and are gearing themselves up for an outing at a sell-out Wembley to face Portsmouth in the Checkatrade Trophy.

Nobody connected with Sunderland will dispute the fact that promotion remains the over-riding priority this season, but having progressed to the final of the Trophy there is a determination to deliver some silverware.

The Wearside outfit’s supporters have clearly bought into it by snapping up all of the tickets made available to them and now the players are really getting into the spirit of things too.

And the only thing on Sunderland’s mind going into the next 11 days is making sure that captain George Honeyman – who is available for the competition despite serving a three-match league ban – gets to hold the Trophy aloft.

Once that has been achieved Sunderland will look to finish off the main job of promotion, knowing the two teams above them – Barnsley and Luton – will have played three games more than them by the time Jack Ross’ side heads to Accrington on April 2.

That does not concern O’Nien. He said: “It’s a big thing to have on your CV. To win promotion last year (with Wycombe Wanderers) was a big thing for me and for the club, so to do it again this year would be special.

“We’ve got the cup final to look forward to first, then nine league games left and every one of those is going to be a cup final.

“We’ve got a chance to be a part of a special season. I know the fans will be there backing us, so it’s very exciting for us.”

It will be Sunderland’s 50th game of the season when they face Portsmouth at Wembley, but there has never been any danger of Ross taking the competition lightly.

O’Nien said: “I didn’t know that but the boys are looking good for 50 games. It’s credit to all the staff that the boys are feeling fresh. We’ve got a very good squad. You probably can’t even remember who started the first game of the season because the squad’s changed all the time.

“We’ve got a hell of a squad here and we’ll need everybody for the final push between now and the end of the season.

“It’s nice to know we can look to Wembley. When you win the semi-final, Wembley’s straight on your mind but we had a couple of games between then and now, so now all our league games are out of the way we’re very much focused on the training building up towards the Wembley game. We’re excited as a club and so are the fanbase.”

O’Nien actually lost in Checkatrade Trophy semi-final with Wycombe before joining Sunderland last summer, but when he made the switch to the North-East he had a funny feeling success was around the corner.

He said: “I knew good things were going to happen but I’m very much looking forward to it. I lost in the semi a couple of years ago so it’s nice to finally get there but we’re not just going there for enjoyment, we’re going to win it.

“We had a game against Walsall last Saturday and we put Wembley out of our minds for that. Walsall was the main focus but now that’s out of the way it’s the Wembley game.  “It’s nice to know that we’ve got ten days or so to put our full focus on the Wembley game. Once that’s out of the way we’ll focus on the next game. For now it’s about making sure we lift that trophy.

O’Nien has effectively nailed down his starting spot as a right-back at Wembley after a string of impressive performances in the last few months.

The 24-year-old arrived as a midfielder capable of playing further forward, but instead Ross has earmarked him for the full-back slot and he looks dangerous every time he goes forward. He also defends well.

“It’s been a good learning curve for me,” said O’Nien. “Playing right-back is not too much different from playing in the middle, you’ve just got to slightly adapt your thinking and your positioning. I’ve got good people around me who are helping me all the time.

“I’ve enjoyed my transition from midfield to right-back and it’s nice to be contributing to the team on a weekend. A lot of people have helped me to build my game and I’ve improved a lot as a person since I’ve come here. Hopefully it can continue for the rest of the season.

“I’ve only been to Wembley as a spectator, I’ve never set foot on the pitch so for me it will be a dream come true to play there, whatever role. For my family and my friends and for everyone in the area it will be a special occasion.

“I know a lot of people booked hotels while we were in the semis, maybe even the quarters, so it was big for the area. It will be a sell-out so it will be a good day for the club and our job is to go out onto the pitch and deliver.”

Sunderland striker Grigg, meanwhile, has been ruled out of Northern Ireland's Euro 2020 qualifiers against Estonia and Belarus.

The 27-year-old has returned to his club and will miss the matches at Windsor Park on Thursday and Sunday. It is hoped he will recover in time for Wembley.

Grigg, capped 13 times by Northern Ireland, has gone back to Sunderland for treatment and it arrived after he was recalled after missing the last three internationals.