Sir Alex Ferguson's past successes at Manchester United stemmed in part from the Scot's deep understanding of who he needed in his squad.
Lent.az, citing foreign media, reports that he often signed players who later became stars. But sometimes there were those who did not live up to expectations.
A prime example is Eric Djemba-Djemba. He was transferred from Nantes in 2003 after a successful run with the Cameroon national team at the African Cup of Nations. Ferguson followed the Cameroonian player for several months and said he was confident that he would contribute to Manchester United's success.
Ferguson said at the time: "He has developed by playing very well for the Cameroon team in the last few months and is in every way a Manchester United player."
Unfortunately, the midfielder was unable to achieve any significant success at Manchester United and was sold to Aston Villa in January 2005 for just £1.5 million as he failed to establish himself in the first team.
The Scottish specialist noted four transfer mistakes in his autobiography "Alex Ferguson: My Autobiography": Eric Djemba-Djemba, Kieran Richardson, William Prunier and Ralph Milne.
He specifically mentioned the latter: "My worst transfer? Ralph Milne. I only paid £170,000, but I still get criticised for it."
Milne joined Manchester United from third division club Bristol in 1988 for £170,000. He was previously a leading player for Jim McLean's Dundee United and was even inducted into the club's "Hall of Fame". But the winger failed to achieve this in Manchester.
He was removed for not remaining loyal to the team and moved to the substitutes. Milne played his last game for Manchester United at the age of 28. Ralph Milne died in 2015 at the age of 54.