Andrew Deighan, 24, handed himself in after his mother had made an anonymous phone call to police, naming him as the killer. Judge Lady Dorrian told Deighan that he must serve a minimum of 14 years before he can apply for parole.
Lady Dorrian told him: “Having been in a fight with others, you returned to your mother’s house where you deliberately armed yourself with a weapon, a bat, before going out… to find someone to attack.”
But Bernard Martin, 48 – who was standing nearby when his son Matthew was fatally injured outside a pub in East Kilbride – described the minimum sentence as a “joke”. He said: “My son was only 20, an innocent by-stander. Now somebody thinks 14 years is enough for him.”
The judge said she accepted that Deighan, who has a record for assault and reckless conduct, was remorseful and had struck only one blow, but noted that he had set out to attack someone.
An earlier trial heard that Deighan had been watching a Rangers v Celtic match on 6 February, 2011. After getting into a fight, he went to his mother’s house for a baseball bat and hat to use as a mask before going out again seeking revenge.
A jury watched CCTV footage of him running towards Matthew Martin and attacking him. Mr Martin, of Ross Place, East Kilbride, staggered away, but his body was found the next day. His skull was smashed and he had suffered fatal brain damage.