McIntosh blames UK work permit laws for such deals failing to materialise.
He told the Mirror: "I remember when I was in Argentina scouting, and I recommended Aguero to Sir Alex's brother, Martin Ferguson, to take him to Manchester United.
"Martin went and saw him play for Independiente against Huracan and Aguero was available for 3.5million as a 17-year-old.
"Aguero has gone on to play for Atletico Madrid and is now at Man City, which is ironic."
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