United offloaded Morrison to West Ham United last January.
"The so-called friends he was knocking around with are not good people and they took him off track," Phil Brogan, who scouted an eight-year-old Morrison for United, told the Mail on Sunday.
"They got him into trouble. He needed to be in a routine away from them and unfortunately that meant getting away from Manchester. Which was a shame because I think he could have lit up Old Trafford."
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