Incensed by an acquaintance's taunts, former gang member Thennarasu Karupiah, 50, rained blows on the man's body and head even as onlookers tried to stop him.
When the man fell to the ground and gestured for him to stop, Thennarasu grabbed a metal chair and hit him repeatedly with it.
He even stomped forcefully on the man's face thrice, after the victim had slumped to the floor .
The assault in July 2016 proved fatal and the man later died.
Yesterday, Thennarasu was sentenced to 15 years and five months in jail after he pleaded guilty at the High Court to culpable homicide not amounting to murder.
The court heard that Thennarasu and the victim, Mr Arokiasamy Paul Rajoo, then 55, had known each other since the 1980s as they were both members of secret societies.
Both were at the Taj Mahal Bollywood Music Lounge in the early hours of July 13, 2016, said Deputy Public Prosecutor Dwayne Lum.
Mr Arokiasamy asked Thennarasu why their old gang had not helped him when he was robbed the previous week. Thennarasu claimed he did not know about the robbery and the two argued, said DPP Lum.
Mr Arokiasamy then questioned Thennarasu's parentage, and Thennarasu threw the first punch at Mr Arokiasamy's face. They fought, with Thennarasu at one point picking up a metal chair to bash Mr Arokiasamy repeatedly, said DPP Lum.
Mr Arokiasamy was taken to Singapore General Hospital, where he was operated on to remove blood clots in his skull. He also had skull fractures and bruising of the brain. He died on July 16 that year.
In mitigation, Thennarasu's defence counsel Thangavelu called for Thennarasu to be given eight to 10 years' jail. "He did not spoil for a fight, there was no animosity, no reason for him to assault... except for that split second... when the victim uttered vulgarities and insulted his mother," said Mr Thangavelu.
However, Justice Hoo Sheau Peng deemed the acts violent and brutal, and said there were many opportunities for Thennarasu to disengage.
For culpable homicide, Thennarasu could have been jailed for up to 20 years and fined or caned.