SUNDERLAND last night offered an olive branch to stay-away striker David Bellion as they demanded a Premier League probe into his proposed move to Manchester United.

The Wearsiders have reported United to the top-flight authority, claiming the unsettling effect they have had on the French youngster is tantamount to an illegal approach.

Bellion, rated at £3m, was yesterday still officially AWOL after Sunderland sent him to the National Sports Centre at Lilleshall for a rehabilitation course aimed at solving what were described as "mystery'' injuries.

The 20-year-old checked out of Lilleshall and returned to France on the pretext that his mother was ill and he was "mentally not right'' to play.

Sunderland chairman Bob Murray yesterday dismissed as "absolute rubbish'' by Bellion's agent Mike Morris that the player was on his way back to Wearside and "totally committed'' to the club for the rest of the season.

Bellion, who turned down a new three-year deal which Sunderland say would have guaranteed him a "500 per cent pay rise'', is out of contract this summer and wanted by United manager Sir Alex Ferguson.

Sunderland entered into talks with United in an attempt to thrash out a deal within the transfer window.

United have since offered a down payment of £500,000 rising to £1m, way short of Sunderland's valuation.

And last night United released a statement refuting claims of an illegal approach.

It read: ''We formally contacted Sunderland in December on the basis that David Bellion was going to be out of contract this summer and with the intention of establishing whether we could reach agreement with the club on a deal for the end of the season.

''We have played no part in making the player feel disaffected with Sunderland and at no time have we made an illegal approach for him.''

The Black Cats will be entitled to compensation for Bellion at the end of the season because he is under 24 and they have helped develop his talent in the 18 months since he was signed by former boss Peter Reid from Cannes on a free transfer.

A tribunal will decide how much Sunderland should receive, but Monaco-based Morris insisted that Bellion is now leaning towards a move back to France, with Paris St. Germain, Lens and Lyon showing interest.

And Morris warned Sunderland they would only receive around £120,000 under FIFA rules if Bellion moved abroad.

In the meantime, Sunderland manager Howard Wilkinson, who succeeded the sacked Reid in October, is desperate to have the quicksilver Bellion available to boost his side's desperate fight against relegation.

And a senior source at Sunderland last night urged Bellion to "come back and make yourself a hero''. Bellion has not figured since appearing as a substitute in the 2-2 draw at West Brom four days before Christmas.

A Sunderland spokesperson said: "David Bellion said he couldn't play on Boxing Day (in the 2-1 home defeat by Leeds) because of a problem with the ball of his foot, but our medical people couldn't find anything wrong with it.

"Then he had a problem with a heel, then he had a cold which became flu.

"He is out of contract this summer but seems to think he can leave immediately as a free agent. Mentally, he is already at Manchester United.

"But we'd like him to come back and make himself a hero until the end of the season.

"If he wants to play for Sunderland and help us get out of the bottom three, then he will go to Man. United with our blessing. He has the right to make that decision in the summer.''

Murray has accused United of "despicable'' and "shabby'' conduct over the Bellion affair.

He said: "Considering we are fighting for our lives, their behaviour has been despicable. The relationship between the clubs is at an all-time low.

"We are realistic enough to realise that sometimes you cannot keep a player and we understand why he would want to go to Old Trafford, but they do not want him now.

"Their behaviour has been shabby.

"All they have achieved is to unsettle a player and, as a result, we have lost David for six or seven months of his contract at a crucial time.

"We're fighting for our lives, United are the biggest club in the world and they pull this one on us.''

Murray, who has confirmed interest in Bellion from Liverpool, Arsenal and PSG, added: "Howard's view, having had the opportunity to work with David, is that he's a talented young player with pace who can add new dimensions to our game.

"David certainly features in Howard's plans and he's been given opportunities. He has not played for us since before Christmas, which is extremely disappointing given our current position.

"I feel very sorry for David as he has always been a dedicated, honest and affable player. He is young and it appears he has been manipulated and influenced by agents.

"David first made us aware that he had an injury just before Christmas, about the same time speculation arose regarding Manchester United's interest in him.

"Since then he's advised the club that he's unable to play because of further injuries, none of which have shown up in our medical tests or scans, so we agreed to send him to Lilleshall for more specialist attention.

"United are only too aware of the club's current position and the effect losing a valuable player at this time could have on us. Their approach has been unethical and uncaring."

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