Labourer Alan Storie, 26, murdered David Findlay on June 29 last year, at Toryglen Road, Rutherglen.
Yesterday at the High Court in Glasgow judge Lord Bonomy sentenced Storie to life imprisonment and ordered him to serve at least 16 years behind bars before being eligible for parole.
Jailing Storie, judge Lord Bonomy told him: "Nothing I've heard here or during the trial can begin to explain the callous and vindictive attack on David Findlay, essentially slashing him outside his own home."
The court heard that a row developed after Storie went to see if Mr Findlay wanted to played on the X-box with him and was asked to leave.
The men had words outside the flats at 2.10am and Mr Findlay made derogatory remarks about Storie's hair colour. The Crown say it was at this point the fatal blow was struck.
In evidence father-of-one Storie admitted cutting Mr Findlay with the knife, but claimed he was acting in self-defence.
Advocate depute David Taylor, prosecuting, said Storie has 20 previous convictions at summary level including for assault, domestic violence and police assault.
Defence QC Frances McMenamin told the court Storie was bullied at school because of his hair colour.
She added: "From the age of 13 he was subjected to two significant experiences of bullying at school. These experiences have clearly had a profound impact on him."