Video images of the 18-year-old named only as Torben P., kicking the man in the head as he lay defenceless on the ground, shocked and disgusted the German public.
The attack, in the central Berlin Friedrichstraße underground station in April, helped spark a debate about young people and senseless violence after similar incidents.
Speaking in Berlin's District Court, Judge Uwe Nötzel justified the sentence of two years and ten months, saying that Torben P. was not only very drunk during the attack, but in the mood to provoke. He said the kicks he aimed at the unconscious man's head were deliberate and vicious.
“He understood the danger of the kicks,” said Nötzel, adding that the victim could have died in the attack, and that Torben P. accepted this risk.
He knocked the victim, who 29 at the time, to the ground with a bottle and then kicked him at least four times in the head, leaving him unconscious. “He could have suffocated,” said Nötzel.
Torben P. admitted the attack at the start of the trial, describing his own behaviour as disgraceful and admitting that his drunken state at the time was no excuse.
In another recent incident in the capital, a 23-year-old man died last week after being chased out of an underground station by a group of young men and running into the road where he was hit by a car.