Blake-Faatafa then walked away. Security footage showed him yelling and making gestures towards the man.
About two minutes later, he returned to the motionless figure and stomped on his head a further three times.
Blake-Faatafa called an ambulance but has no recollection of doing so.
The victim was hospitalised with severe head and facial injuries. He had amnesia for 33 days.
The court heard today that he has lost sight in his left eye as a result of nerve damage caused by kicks and stomps to the head. He also has reduced use of his left arm and left leg, requiring a walking stick, and lost some of his fine motor skills.
Blake-Faatafa, of Avondale in Christchurch, was sentenced on two counts of wounding with intent to cause grievous bodily harm, and one earlier count of receiving stolen goods.
Blake-Faatafa's mother was in court to support him today.
Defence counsel Glenn Dixon described the attack as a "drug-fuelled rage".
Blake-Faatafa lost his girlfriend unexpectedly to an aneurism in November last year, causing his P use to increase.
As his drug use took over, he lost his job, Mr Dixon said.
He has an acknowledged anger problem and is struggling with his grief, he added.
Mr Dixon said he also had "genuine and significant remorse".
Judge Neave described the attack as "one of the most serious offences of its type".
It amounted to "utterly appalling" extreme violence, he said.
The victim has written a "very forgiving" victim impact statement, the judge said.
The victim said it was "very sad" that Blake-Faatafa didn't seem to know right from wrong.
"You robbed him of his full enjoyment of life," Judge Neave told an emotional Blake-Faatafa in the dock.
Judge Neave took time off the jail term of eight years and seven months for an early plea, his relative youth, and a willingness to address his issues.
He also said that it was "one of those rare cases" where he should impose a minimum non-parole period, which amounted to four years and three months.
