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West Ham boss Sam Allardyce believes he signed a boy in former Manchester United teenager Ravel Morrison but that the midfielder will return to Old Trafford on Saturday as a man.
The 20-year-old was one of the stars of United's fabled youth system but was limited to just three first-team outings for the Red Devils as his life off of the field began to overshadow his undoubted talent on it.
A thirst for first-team involvement saw Morrison move to Upton Park and, after a season on loan at Birmingham last year, the precocious talent has started to shine through in the Barclays Premier League.
Morrison is West Ham's top goalscorer this season with five and Allardyce feels the player has developed so much over a short period of time that he will be completely different when he lines up against United for the first time on Saturday.
"Sir Alex [Ferguson] let Ravel go for his own benefit," he said. "He [Ferguson] said that if he comes down to you hopefully he will find a new life and a new way of living.
"His ability will then start to come through because all he asks and all he wants in his life is to play first-team football, that was all he said he wanted to do and why he wanted to leave.
"In actual fact he struggled to look like he was capable of playing football in the first team with us. That's why we sent him on loan to Birmingham and I thought since that year he's grown up.
"Somewhere along the line the lad has woken up and I think he's changed himself and delivered."
Allardyce admitted it was Ferguson's expectation of the player Morrison could become that was the simple deciding factor on his striking a deal to take the player to east London.
"Fergie told me about his talent and that was it," he said.
"That's enough for me.
"[Ferguson said] 'if you can sort this lad out, Sam, you'll have one of the best players you've ever had'. I don't need anything more than that do I?"
Morrison has been a shining light in an underwhelming season so far for West Ham, who will be hoping Wednesday's 2-1 Capital One Cup quarter-final success at Tottenham can kick-start their league campaign.
But even Morrison has off days and Allardyce is keen to keep him focused and unlock the match-winning potential as often as possible, with a warning that he should not try and steal the show against his former club.
"The expectation becomes "will it come every single week" and that can't really happen at such a young age," Allardyce added.
"It's nice if it does. We've got to manage the situation and just try and keep encouraging him.
"I think from our point of view, if he gets selected for Old Trafford on Saturday, that the real message from me to him would be to try and get a result as a team and play one of your top performances in a team situation when you would help to get us that result buy using your abilities in a team performance.
"When you've got his ability there is going to be the temptation to go out and go 'look at me' I think and I have to try and guard and avoid that situation."
Morrison is likely to feature after starting on the bench against Spurs and, with captain Kevin Nolan still suspended - and a host of other first-team players sidelined or working back to full fitness - Allardyce is limited in terms of options.