Rio Ferdinand, who was recently released by Queens Park Rangers and lost his wife Rebecca to breast cancer on May 1, retired from football on Saturday aged 36 saying it was "the right time" to leave "the game I love", in a statement read out on BT Sport.
The East London-born star had 12 trophy-filled years at Manchester United after twice breaking the transfer record for a defender when he moved from West Ham to Leeds United for £18 million in 2000 and then the Red Devils for £30 million two years later.
Ferdinand played 81 times for England and is widely considered to be one of the best defenders of the modern era.
But the man who brought him through his boyhood club West Ham's famous Academy says his career could well have taken a different path after he first spotted the gangly 14-year-old's immense talent at Upton Park.
"I knew straight away that he had the ability to be the best central defender in Europe," Redknapp said writing in his column in The Sun.
"I'm not exaggerating. He was that good (as a 14-year-old) and he deserves to be ranked up there with the very best.
"Rio had it all - pace, strength, distribution, fantastic temperament and he was a brilliant reader of the game.
"He could just as easily have been a world-class midfielder but he was such a terrific defender that it seemed best to leave him where he was most comfortable."
Ferdinand has remained a firm favourite with Hammers fans throughout his career after he emerged through the club's Academy ranks being billed their best defender since the legendary Bobby Moore.
He made his Premier League debut in 1996 and went on to win the prestigious Hammer of the Year award the following season.
He earned his first senior international cap in a match against Cameroon in 1997, setting a record as the youngest defender to play for England at the time.
Ferdinand further endeared himself to the West Ham fans when he famously cried after being told his boyhood club had accepted the record breaking offer from Leeds. And when he scored against his old club for the Elland Road outfit he refused to celebrate.
The feeling of admiration between Ferdinand and Redknapp is mutual after their time together in East London.
Speaking about his career in an interview back in 2008, Ferdinand said of his old West Ham boss, quoted by the Daily Mail: "Harry was my inspiration, the manager who took a chance on a gangly, slightly awkward teenager and gave me the momentum to become a Premier League and Champions League winner, and an England international."