Alex Ferguson and senior figures in the Manchester United dressing-room will take Wayne Rooney under their wing to ensure there is no repeat of the lurid off-field stories which darkened his last days as an Everton player and ultimately drove him away from Merseyside.

Rooney was unveiled as United's new £27 million number eight at Old Trafford yesterday and insisted he had matured on and off the pitch over the last year despite allegations, backed up by closed-circuit television footage, that he had visited brothels in Liverpool. Yet Ferguson will shield the 18-year-old, as he did the young Ryan Giggs and David Beckham, to ensure England's youngest ever goalscorer fulfils his talent.

"We'll put a guarding arm around Wayne, as we have to with all the players," said Ferguson. "Wayne will get the same advice and protection. In that dressing-room there is security. People like Roy Keane, Paul Scholes, the Nevilles and Ryan Giggs are all mature, stable professionals. Wayne will see these players and how they have grown into what they are today.

"That's not by accident. He is coming to the club who can handle most things because we get the most attention. It is more difficult for players now because of the profile they have. When they walk down the street they get photographed, not just by the press but people can take a photo with their mobile phones and there is nothing you can do about it, so there is tremendous pressure on young players. But the players here have good reputations; they are professional, we look after them well, and I don't see it as a problem with Wayne."

Rooney was deeply upset by the revelations about his private life which tarnished his last few weeks at Goodison Park, though Ferguson offered him a whispered "well done" when he insisted his new manager would not need to make him a special case.

"I don't think he has to say anything to me," said the teenager, flanked by his agent Paul Stretford and his fiancee Coleen McLoughlin, when asked what Ferguson had said to him about how a United player should conduct himself. "As a professional footballer, I know myself. No one has to tell me how to behave on or off the pitch."

The fallout from Rooney's transfer was still juddering across Merseyside yesterday. The chairman Bill Kenwright claimed he was still "numb" from the sale, though the player himself was quick to insist that he, rather than Stretford, had instigated the switch.

"I made my mind up six weeks ago that I wanted to leave Everton," said Rooney, who has signed a six-year contract worth over £50,000 a week. He will undergo a scan on his broken metatarsal today and is rated at three weeks away from returning to full fitness.

"It is tough for Evertonians because they see me as one of their own, but I want to move on for myself and I see no better place than here. After Euro 2004 I made my mind up that I wanted to play for a bigger club. I knew I could play with top players in big tournaments and I wanted to do that at club level. I was sitting with England and all the other players were talking about who they've got in the Champions League on Wednesday. I want to be playing there in the biggest club tournament in the world. If Everton had been in the Champions League, it would have been a different matter.

"The spotlight is going to be on me more because I have just signed for one of the biggest, if not the biggest, clubs in the world. There is going to be a lot more pressure, but I am big enough and strong enough to handle it."