Mitchell Gibbons, who was 20 at the time, was enjoying a night out with friends when an argument broke out in Preston city centre, police said.
Mohammed Aseeb Ali, 23, proceeded to punch Mitchell once in the head, knocking him unconscious.
As Mitchell lay unconscious on the ground, Uzair Bhatti, 31, kicked him twice in the head before spitting on him.
Dhanyal Hussain, 22, then helped Ali and Bhatti get away from the scene by reversing his car down a one-way street.
The vicious attack happened in February 2020.
Mitchell remained in a coma for 12 days, and required extensive surgery to have half of his skull removed to alleviate pressure on his brain.
He was left with permanent scarring and went through months of rehabilitation to help him to learn to walk and talk again.
In a victim impact statement read to the court, Mitchell said the attack had destroyed his confidence and ruined his dream of racing a bike in the Isle of Man TT race.
He also said he had been left self-conscious about his appearance.
Ali, from Cornelian Street, Blackburn, and Bhatti, from Calder Banks, Blackburn, were given a two-year jail term, suspended for 18 months, after they admitted wounding.
They were also given 180 hours unpaid work.
Hussain, from Whalley Range, Blackburn, was sentenced to four months imprisonment, suspended, for assisting an offender.