LUKE O'Nien says Sunderland's understandable early season uncertainty has been replaced by belief, with the Black Cats intent on grasping their opportunity at the top end of the Championship.

After four seasons in League One, O'Nien says it was inevitable that Sunderland would have to feel their way into the season and get to grips with second tier life once more.

But with a little over half of the season now played, the 28-year-old believes Sunderland are in the promotion mix on merit - and is desperate to stay there.

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"I think at the start naturally you are uncertain a little bit and I think anyone would be, because some people have played in this league and some people haven’t," he says.

"I think you learn to grow into it and a lot of us have. With that growth and belief I’ve got no surprise where we are right now because collectively we work really, really hard and learn game by game.

"Maybe at the start of the season you have the element of this is a new league, and now that’s gone. I really believe and back where we are and think we’ve deserved to be where we are and we just have to keep pushing forward.

"We are just enjoying our football and you can see that in the way we are playing. There was a huge belief at Blackpool that we should have come out in the second half and generally I feel we should have won three or 4-1.

"We are going into games and I don’t think we have really played a team which has dominated us. We’ve been competitive every game and we’ve been there to take the points.

"We are in a real good position to kick on this year and just have to make sure we take the league in our own hands, we don't just wait for it to happen, we make it happen and I think we are doing that so far."

O'Nien says the fact Sunderland came away from Blackpool disappointed - despite having picked up seven points from nine during the Christmas and New Year week - is evidence of their progress.

"I think it shows how far we’ve come especially when you get seven points from nine," he said.

"We walk away and we should have had more, and we wanted more, and we feel like we deserved more.

"I think that’s credit to us because everybody connected with Sunderland has been working so hard and putting all the work in behind the scenes.

"We just have to make sure we keep getting better every game that goes by, learn, and even the games we win take away our good points and make them better. It’s an enjoyable place to be."

O'Nien was one of the Sunderland players who suffered with illness between the Wigan and Blackpool games and dragged himself out of bed to feature at Bloomfield Road.

He said: "It wasn’t ideal. I was in bed all day (on Saturday) for training so I missed that.

"I managed to catch up with the tactical side on the morning and just get out there and still play, still help the boys."

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With Sunderland's squad decimated by injuries in recent weeks, O'Nien's versatility has once again come in extremely handy, with the former Wycome man playing on the left of a back three.

"I enjoy it down the left side, especially when you’ve got Clarkey there," he says

"I give the ball to him and watch his dancing feet, and then I’ve just got to defend. I have Bails inside me who makes my job really easy.

"I enjoy it and it’s our job to keep the ball out of the net. We didn’t quite get the clean sheet we wanted (at Blackpool), but we’ll look at the whole game and see how we can come away with three points next time."