Mark Corcoran, 26, died at Subitha Food and Wine shop on Whitehorse Lane, near Crystal Palace FC ground, Selhurst Park.
It is believed Mr. Corcoran, from Croydon, was stabbed within 100 yards of the shop at about 8.20pm before staggering there for help. Emergency services were called but Mr. Corcoran was pronounced dead at the scene.
The murder investigation is headed by Detective Chief Inspector Cliff Lyons, from the Homicide and Serious Crime Command in Lewisham.
DCI Lyons said: “We know that Mr. Corcoran attended a wedding on Valentine’s Day and we are appealing for anyone who has knowledge of his attendance at this wedding or his movements throughout the day to come forward.
“We would also like to hear from anyone who was in the area of the Crystal Palace football ground, particularly after 7.30pm, who may have seen or heard anything.”
At this stage the police are keeping an open mind regarding any motive for the assault.
Initial enquiries led to the arrest of a man in his forties two days after the killing. He has been released on police bail until mid-March.
Three potential witnesses who are visible in CCTV footage from the shop have also been traced after an appeal last week.
Anyone with information should call police on 020 8721 4961, or can call Crimestoppers anonymously on 0800 555 111.