NEWCASTLE United centre-back Andy O'Brien has admitted that the much-maligned Magpies defence is struggling to shake off what he sees as an unwarranted tag of under-achievers.

Graeme Souness's side head to Selhurst Park tomorrow aiming to remedy a run of form that has seen them lose four consecutive domestic games - including three home defeats in a week when nine goals were conceded.

The whole side has come in for criticism, but O'Brien launched a spirited defence of the back-line.

"It is frustrating, but you've got to be strong mentally and physically and cope with that," said O'Brien, whose hamstring injury means he misses out at Crystal Palace tomorrow.

"I wouldn't say we're constantly under fire. People have had this impression about it and it's proving difficult to shake off, but we've had some good seasons over the three-and-a-half years I've been here and I'm determined that, hopefully, we can better them.

"If we do better them, you could say that we'd be playing regularly in the Champions League, and we have the potential to do that.

"Players that are playing in the team are giving their all. There's talk about maybe a centre-half coming in. That isn't my decision, but my principles are the same. I'll work hard and give of my best and if I make a mistake, I'll try to correct that if I can."

Souness is continually linked with some of Europe's top centre-backs, with reports indicating he has tabled bids for both Rangers' Jean-Alain Boumsong and Manchester United's John O'Shea.

But 25-year-old O'Brien is backing those already at the club to show they have the necessary experience and quality to turn things round.

"It's difficult in the centre-half position. But all I'd say is that it's important to support the four that are there," said O'Brien, who has himself been linked with Championship leaders Wigan Athletic, managed by his boss at Bradford City, Paul Jewell.

"They're all good players. I'd like to think I'm an OK player, playing international football for a good country, Aaron Hughes is captain of his country, Olivier Bernard, I would say, is not far away from the French squad, and Titus has the potential - he's only young - to play for England.

"There's a hell of a lot of potential there and it needs support from time to time.

"But the other side of the coin is that the player has to be strong mentally and physically.

"We're all learning because we're only young, but hopefully we'll be given time to mature into what people believe we will be. That's why we were brought to the club."

O'Brien believes the criticism the defence receive is not backed up by the statistics, which last season showed them to be the fifth best in the Premiership.

O'Brien said: "It's difficult me standing here trying to defend the criticism about the defence because we've conceded too many goals. But we didn't get credit last year when he had the best home record, and the year before that.

"You have to take that into consideration. We are disappointed we've conceded so many, but we're hopefully going to improve on that.

"It's very frustrating. It's frustrating at the moment because we have conceded too many goals.

"The table doesn't lie, we have maybe the second worst defensive record. I can stand here and say 'What about the previous years?'

"It seems that we're forever having to remind people about that.

"I've said before that Middlesbrough's defence last year was regarded as very strong and they didn't score enough goals.

"We conceded a hell of a lot fewer goals than Middlesbrough, but our players were not spoken about in the same sort of breath."

* Rangers have apparently told the Magpies they want £10m for French international Boumsong. Souness travelled to Paris with first-team coach Dean Saunders to watch the Rangers defender play for France in the 0-0 draw with Poland on Wednesday night.

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