STEVE McClaren is too young to lie back and think of England and should concentrate on bringing more glory to Middlesbrough, according to one of his former colleagues.

Former Manchester United youth coach Eric Harrison witnessed first hand the Boro boss' rise to prominence under the stewardship of Sir Alex Ferguson at Old Trafford.

But while he believes McClaren, number two to Sven-Goran Eriksson in the England set-up and widely tipped as his successor, has the credentials necessary to manage at the highest level, Harrison has urged the 44-year-old to commit himself to the Riverside for a few more years yet.

McClaren has agreed terms on a new four-year deal and Harrison, who nurtured the famous class of '92 that included Paul Scholes, Ryan Giggs, the Neville brothers, Nicky Butt and David Beckham at United, hopes he does.

"I think he is capable of managing England, but, while this sounds silly, I think he is too young to do that," he said.

"It's OK for Sven, who is a little bit older anyway and probably doesn't want to be at it day in and day out, but Steve is guy who needs to be on the training pitch every day."

Harrison, who was at Redcar Town Football Club along with England legend Sir Geoff Hurst as part of a coaching scheme run by McDonald's, says it was clear during his time at Old Trafford that McClaren would one day emerge from the shadows of the now legendary Ferguson.

"He has always been very, very ambitious, although he never broadcast the fact. He is a very clever, studious coach. He thinks an awful lot about what he is doing and his preparation is first class," said Harrison, adding that Boro chairman Steve Gibson would do well to pull out all the stops to ensure he remains.

"I think he can only go upwards and onwards and hopefully it's with Middlesbrough and not with England at this moment in time because he would be a sad loss to Middlesbrough."

In his time on Teesside McClaren has turned Boro into perennial European hopefuls and led them to their first success in a major cup competition when they lifted the Carling Cup in 2004. Harrison is not surprised at the impact he has had since arriving at the club in 2001.

"He obviously learned a lot from Manchester United and Sir Alex Ferguson. They worked very, very closely together," said Harrison.

"In his own right he is now becoming a top manager and he can only get better, I am sure about that. What he has done so far has been excellent.

"I think it will be very, very difficult, no matter how long he stays there, to win the Premier League.

"I think it will be very difficult to win the Champions League, but he has already done very well in Europe and he has won the Carling Cup. If can continue along those lines he will have been a massive success."

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