At nightlife complex St James Power Station, partygoers were leaving when they heard shouting at nearly 6am yesterday.
"Someone shouted that a man was being stabbed," said an eyewitness who owns Postbar, one of the outlets at St James, and wants to be known only as Ms Daisy, 37.
"I turned and saw a bloodied man on the road with his friend," she told The Straits Times, adding that one man was on the ground while the other fell soon after.
"I ran towards them but, by then, the culprit was not in sight," she said, noting that the incident occurred some 20m from her club, one of the outlets where the men had been drinking earlier that night.
Police later said two men, aged 28 and 34, were found injured near a nightspot at St James yesterday morning and were taken to Singapore General Hospital.
The 34-year-old - Mr Sateesh Kumar - sustained stab wounds to his head and back, and was pronounced dead at about 6.45am. The other suffered injuries to his head and has been warded for treatment.
The police have classified the case as murder, and investigations are now ongoing.
A Postbar client who wanted to be known only as Mr Vicky, 33, said he had seen Mr Sateesh in an "argument" with the club's security staff earlier that night, but had not thought much about it. Ms Daisy said no argument had taken place.
Mr Vicky said that just before the stabbing, he was waiting by the road for a cab when he saw Mr Sateesh talking loudly with others in an alley.
"I then heard a man's shout and the sound of metal clanging against something. Everything happened in one to two minutes," he said.
Seow Bei Yi