LEEDS and Crystal Palace are heading a list of Championship clubs who have shown an interest in transfer-listed Sean Thornton, but the Sunderland midfielder is also pondering a surprise offer to resurrect his career in Spain.

Thornton, who made 20 appearances for the Black Cast last season, has been told he has no future at the Stadium of Light as Mick McCarthy shapes his squad for the Premiership.

But, while the 22-year-old is surplus to requirements on Wearside, his agent claims his services remain in demand both at home and abroad.

"A number of Championship clubs have shown an interest in Sean," claimed his agent, Lee Payne. "But Leeds and Crystal Palace are the two that have been in contact the most.

"Both clubs have hinted they want Sean on board and I think it will probably come down to how their budgets are looking later in the summer.

"There has also been interest from abroad though. A couple of Spanish clubs have been in touch, with Malaga declaring a firm interest. That's a definite possibility although, at the moment, I think Sean would rather stay in England."

Great things were expected from Thornton when he joined Sunderland from Tranmere in July 2002.

But, while his on-field performances have made him a favourite amongst the Black Cats fans, his off-field indiscretions have been received rather less warmly by McCarthy and his team.

The Sunderland boss criticised his lack of match fitness at the start of last season, and is understood to have become exasperated by a general lack of direction that culminated in the midfielder missing a Republic of Ireland Under-21s training camp last month.

Thornton is almost certain to leave Sunderland in the next two months but, even if a new employer cannot be found, McCarthy has told him he will not be offered a temporary reprieve.

"When Mick told Sean he was putting him on the transfer list, his first reaction was that he wanted to stay," said Payne. "But the manager said 'There's no point - I'm not going to use you and, if you come back, I'll stick you with the kids. You're not in my plans.

"Sean's been left devastated. He doesn't want to leave - he's never wanted to leave Sunderland - but he's been backed into a corner and left with no choice.

"He's basically paying the price for being a larger than life figure. Maybe if he didn't have the blonde hair and the earrings none of this would have happened."

Last year, Thornton was linked with a move to Everton that failed to materialise and Payne has admitted that things would be far easier this summer if Sunderland were to let his player move for free - something the club are understandably loath to do.

"It obviously doesn't help the situation when they seem to be holding out for a fee," he said. "There are about 150 to 200 players available on a free transfer at the moment, but I think the Sunderland board are hoping to get about £250,000 before they'll let Sean go.

"That's holding the whole process up."

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