Gary Charles and Roy Keane played together at Nottingham Forest. Both were highly-rated by Brian Clough, yet as Keane went on to become one of the most important players in the Premier League's history, Charles life took a downward spiral. In 1992, a teenage cyclist was killed when he collided with Charles' car. Charles was absolved of any blame but the legacy of the horror accident drove Charles to alcoholism.
While Charles maintained a decent career - playing with Derby, Aston Villa, Benfica, and West Ham - things got worse upon his retirement in 2002. He was sentenced to four months in prison in 2004 for drink-driving and a year later was given a one-year sentence for threatening a nightclub bouncer. He entered the Rutland Centre a year later.
It was while Charles was there that he received a letter from his old teammate Keane, as elucidated by Simon Austin of the excellent Training Ground Guru blog.
Keane's letter was lengthy, including the line "There but for the grace of god - what happened to you could have been me". Keane was the manager of Sunderland at the time, and offered Charles a role with the club to help him earn his coaching badges along with a bed at his family home. Charles took Keane up on the offer - and even occasionally took part in training at the club.
Charles has since earned his UEFA A Licence and has gone on to be Director of Football at the University of Nottingham. Most recently, he was appointed manager of Nuneaton Town before being replaced this summer.
Keane has never spoken publicly about the tale, and while Charles has confirmed it, has been unwilling to delve into it in too much detail.