Jim Torbett, who is already serving a six-year sentence for abusing six teenage boys, was convicted of repeatedly indecently assaulting the 13-year-old boy in 1967.
Sentencing him at a court in Inverness, northeast Scotland, judge Andrew Cubie told 75-year-old Torbett that the impact of the attacks had been “lifelong” on his victim.
“You caused significant damage, incalculable harm and blighted his life,” the judge added, according to Scottish media.
Torbett’s offending comes after a string of convictions of junior football coaches in England for a catalogue of abuse against young players.
In 2021, an independent review of historical sexual abuse said the English Football Association demonstrated inexcusable “institutional failings” by not implementing child safeguarding measures.
A separate report in Scotland in the same year called for Scottish football clubs to make an “unreserved” public apology to those who suffered sex abuse at clubs from the 1970s onwards.
Torbett created the Celtic Boys Club, which is closely associated with the Scottish Premier League side Celtic, in 1966.
He was first jailed for two years in 1998 for abusing three young Celtic Boys Club players between 1967 and 1974.
He had been living in California when the latest allegations emerged and was arrested upon his return to Scotland after a BBC documentary expose.
In 2018 he was jailed for six years for a string of sexual assaults against six young boys between 1970 and 1994.
Cubie said Torbett had used the football team “as an elaborate front for recruitment of your young victims”.
AFP
