GRAEME Souness was last night looking forward to one of the "biggest challenges" of his career as the effects of his appointment as Newcastle United boss were already being felt on Tyneside.

Newcastle's week-long search for Sir Bobby Robson's successor ended yesterday morning when Souness opted to leave Ewood Park after four and a half years as Blackburn boss.

The former Middlesbrough and Liverpool midfielder will not take over at St James' Park until next Monday, avoiding a potentially explosive situation when Newcastle and Blackburn meet this weekend.

But, with his appointment almost certain to herald the end of John Carver's six-year involvement with United's backroom staff, the club could find themselves without an experienced hand for Saturday's Premiership clash.

Carver will be asked to take control of first-team affairs but, should Robson's former number two opt to leave his post this week, Alan Shearer could find himself leading the Magpies against one of his former clubs.

Sources in Blackburn are adamant that Souness will want to bring his own backroom staff with him next week, leaving no room for either Carver or chief scout Charlie Woods.

Former Darlington and Hartlepool boss Alan Murray is expected to accompany Souness to Newcastle as his number two, with ex-Middlesbrough player Phil Boersma and former Liverpool striker Dean Saunders also set to be given roles on United's backroom staff.

Shearer confirmed last week that he had no desire to move into management at the moment, but the United skipper could find himself pressed into the role this weekend before returning to his playing duties when Souness is officially unveiled on Monday.

The first inkling of the Scotsman's appointment came yesterday morning when he drove to Blackburn's training ground to tell the club's shellshocked players that he was leaving his post.

Two hours later, Newcastle confirmed that he had been appointed as the club's new manager, with his first game in charge being next Thursday's UEFA Cup first round first leg against Israeli side Hapoel Bnei Sakhnin.

"I'm sad to leave Blackburn because I've had a great four and a half years there," said Souness, who has also had managerial spells in charge of Rangers, Liverpool, Galatasaray, Southampton, Torino and Benfica.

"But I'm joining one of the biggest clubs around and I hope people here (at Blackburn) understand my reasons for going.

"I'm ready for what is a big challenge, and they don't come much bigger. I'm excited by it and I don't need to be told by anyone about the challenge ahead. It's a massively supported club, one of the best around, and everything there is geared for success."

Souness' appointment ends a week of frenzied speculation that had seen more than half a dozen candidates emerge as likely successors to Robson.

Steve McClaren was quick to commit himself to Middlesbrough, while Birmingham's compensation claims ultimately ruled out any move for Steve Bruce.

Terry Venables, Ottmar Hitzfeld and Glenn Hoddle were all interviewed late last week, while Shepherd spoke to former Southampton boss Gordon Strachan last weekend.

David O'Leary and Sam Allardyce were also in the running but, ultimately, Souness' reputation as a no-nonsense hardliner won the day.

Shepherd grew increasingly disillusioned at Robson's inability to curb the excesses of Newcastle's younger element, and the appointment of Souness represents an attempt to bring some order back to the St James' Park dressing room.

The Scotsman has endured similar problems at Ewood Park, falling out with both David Dunn and Dwight Yorke because of their well-publicised personal lives.

Souness is unlikely to be any more sympathetic to the likes of Kieron Dyer and Craig Bellamy, although Blackburn goalkeeper Brad Friedel has insisted that he has mellowed over the last 12 months.

"Everyone thinks he is a big hard man, but they won't see that up there," said the American international, who will line up against Newcastle in four days' time.

"He's more mellow and quiet than he used to be, but he will mould the team into what he wants it to be. I wish him the best of luck winning trophies."

One piece of silverware will do for a Newcastle support that has been starved of success for more than 35 years, but the early signs suggest they are far from sure that Souness can deliver.

Opinion on Tyneside was divided yesterday, although most fans agreed that Souness was not the kind of big name they were hoping for when Robson was sacked last week.

Blackburn have won just six of the 24 league games they have played in 2004, and Souness leaves one of just three clubs currently below the Magpies in the Premiership table.

Tony Parkes has been unveiled as Blackburn's caretaker boss, although former Hartlepool manager Mike Newell - now at Luton - has already been installed as one of the favourites to replace the new Newcastle boss on a permanent basis.

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