REPUBLIC of Ireland veteran Niall Quinn has warned his Sunderland team-mates that defeat against Southampton this afternoon could prove "catastrophic" in the battle for Premiership survival.

A double for Gordon Strachan's men would leave the Wearsiders with a formidable seven-game run-in, including three away against teams chasing European qualification and a home match against Championship-challenging Liverpool.

Quinn is certain that Sunderland have the quality to fight their way clear of a relegation dog-fight - but stresses that nothing can be taken for granted by a team just four points clear of third bottom spot, with the fourth worst goal difference of the strugglers.

Club captain Quinn said: "The main thing is that there is still tremendous belief in the squad and we know we are capable of much better things than we've produced this season.

"The Southampton game now becomes so huge that nobody should need lifting for it.

"We really have got to get stuck into them. We can't sit and wait and look at other teams now - we've got to post three points on the board very quickly and the game against Southampton is one we must win. Three points against them would leave a lot of clubs looking up to us and it is a massive game. People are dejected, but we can pick them up.

"Winning is the only thing on our minds, but we know that a defeat could be catastrophic."

Quinn, who has been confined to a substitute role in the three games since loan signing Patrick Mboma came into the side, is still confident that for all the disappointments of the season Sunderland could still come good.

He said: "Rather than moan and groan we've got to get on with it and find the key to unlock the door. I would like to think we could finish the season strongly."

England striker Kevin Phillips, missing at Chelsea with a knee strain, is set to resume his partnership with the big Cameroon international and will be looking to end a four game run without a goal against the club which showed him the door as a teenager. But he admitted last night there is still a niggling doubt about the injury which cost him his ever-present record at Chelsea.

He said: "I really want to play against Southampton and unless the injury worsens I expect to be involved. I've got a muscle tear above my knee and they are difficult to judge in terms of recovery.

"If I'd played against Chelsea last week and the injury had worsened then I would have been looking at two or probably three weeks out of the side and we didn't want to risk that at this stage of the season. I could still feel the strain when I trained yesterday but it wasn't as bad as it's been and the next 24 hours are crucial to see how it reacts.

"If the worst comes to the worst and it really stiffens up then I probably won't be involved - but I'm quite optimistic that that won't happen."

Crowd favourite Phillips has been the leading light of Sunderland's return to the Premiership, and his struggle for goals in the current campaign has been one of the main reasons for the club's demise.

He said: "I'm looking forward to playing against because it seems ages since our last home game against Bolton Wanderers and I'm keen to be doing everything I can for the club. It has been a while since I got on the score-sheet and it would be nice if the game against Southampton got me going again."

With players coming back after injury Northern Ireland international George McCartney is hoping to hantg on to the left back position, though manager Peter Reid could decide to opt for the experience of England international Michael Gray, who has played in the last three games on the rig.ht side of midfield.

The 21-year-old Belfast-born defender, who can also play at centre-half, said: "I have been at the club for five years now and left-back is where I have always played. I've always looked up to Michael Gray and I've learnt a lot from him but now I've been given the opportunity to play at left back it is up to me to prove I'm as good as he is."

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