AITOR KARANKA is interested in speaking with Sunderland about the managerial vacancy at the Stadium of Light, but the former Middlesbrough boss would require some cast-iron assurances about the club’s future direction before considering taking the job.

Karanka, who has been out of work since his departure from Boro in March, is keen to return to management and would ideally like to remain in English football.

He is currently on a family break in his native Spain, but retained a base in the North Yorkshire town of Harrogate in the wake of his exit from the Riverside having put down some strong roots during his three-and-a-half years on Teesside.

His track record with Middlesbrough, where he inherited a side close to the Championship relegation zone and led them to a play-off final before securing automatic promotion the following season, means he will almost certainly be of interest to Sunderland chief executive Martin Bain as he looks to appoint a long-term successor to Simon Grayson, who was dismissed on Tuesday night.

Sources close to Karanka claim he would be willing to listen to what Sunderland had to offer, but would have to feel there was a realistic chance of stability and progress before he would agree to take over on Wearside.

The former Real Madrid assistant has turned down offers from Birmingham and Alaves in the last six months because he did not feel that either club was right for him. Birmingham were keen to make him Harry Redknapp’s successor, but the chronic off-field instability at St Andrew’s is understood to have been a major factor in his decision to reject the Blues’ advances.

Sunderland are currently searching for their ninth manager in the last six years, with their owner, Ellis Short, remaining keen to sell despite having taken the club off the market when a potential takeover involving a German consortium was threatening to scupper attempts to recruit a manager in the summer.

However, the Black Cats remain one of the biggest clubs in the Championship and Bain is confident he can appoint someone capable of recapturing former glories.

John O’Shea was the big mover in the betting markets yesterday, with some bookmakers now making the centre-half an odds-on shot to be appointed as boss.

The Irishman has previously spoken of his desire to move into coaching when his playing career ends, and his six-and-a-half year spell at Sunderland means he is an extremely influential figure in the Stadium of Light dressing room.

Short is known to respect him, and he was persuaded to sign a new contract on Wearside this summer even though he had alternative offers from elsewhere, but Bain is understood to regard experience as a key attribute given Sunderland’s current position in the bottom three.

A number of other managers have indicated an interest in succeeding Grayson, but many lack experience in either of the top two divisions.

Wigan boss Paul Cook is understood to be keen on the role, while Shrewsbury’s Paul Hurst has also been touted as a potential contender.

At the other end of the experience scale, Redknapp hinted at a potential interest yesterday when he said: “I am getting bored, I must admit. Sunderland is a great club with great tradition. It shouldn’t be where it is at the moment. It is another club that should be doing a lot better.”

Barnsley manager Paul Heckingbottom, who spent four years on Sunderland’s books as a youngster, has also been linked, but played down talk of a possible return to the North-East yesterday.

“It’s flattering in the respect that things are going well and you can do a job, but other than that, that’s it,” said Heckingbottom. “People in the North-East who I already know are the first to have spoken to me about it, and that’s as far as it goes. Other than being asked about it now, it’s not even in my head.”

Robbie Stockdale and Billy McKinlay were placed in caretaker charge on Wednesday, and have overseen training in the last two days. They will take charge of Sunday’s Tees-Wear derby with Middlesbrough, and could yet be considered for a permanent role if things go well at the weekend.

Stockdale was a player with Boro before moving into coaching, and insists the pressure will be on his former employers in two days’ time.

Speaking prior to Grayson’s dismissal, he said: “Middlesbrough have spent an awful lot of money this summer, and I think there’s a pressure on them to go straight back up. I don’t think there’s any doubt about that.

“They’ll try and play it down, but when you’ve spent the amount of money they have, they should be looking to go straight back up.

“We’ve been better than what our results have suggested. We should have more points on the board, without a doubt. But when it comes to a derby game, I think anything goes. I think the form book goes out of the window.”

Grayson issued a brief statement yesterday morning thanking Sunderland for giving him an opportunity in the summer, and wishing the club all the best.

“I would like to take this opportunity to express my thanks to the club and all the fans, players and staff at the club’s training ground and Stadium of Light,” said Grayson.

“Sunderland AFC is a huge football club and while I am disappointed not to be continuing as its manager, I hope the club will stabilise and return the success and first-class football the supporters and people of Sunderland deserve. I would like to wish everyone associated with Sunderland AFC all the very best for the future.”