Two men are facing jail after they were caught on film attacking a homeless man, who later died, while on a night out.
The pair punched and kicked the 51-year-old during the attack at midnight on 3 June 2017, the Old Bailey heard.
Mr O’Beirne had initially threatened to “shank” the two workmates after they told him they had no cigarettes.
But he was walking away when Antunes, 21, landed a punch, that knocked him to the ground, and Abella, 22, appeared to follow up with a kick. He suffered a traumatic brain injury and died six months later on 20 December.
Antunes, of Tottenham, pleaded guilty to manslaughter earlier this month. His co-defendant, from Lambeth, admitted attempted assault occasioning actual bodily harm during a brief hearing on Friday.
The pair will now be sentenced on 8 February.
Bailing Abella, Judge Wendy Joseph QC said: “Do not read into that any indication of what the sentence might be at the end.”
Earlier this year, police released images of the attack and offered £20,000 to anyone who could help them track down the culprits.
Mr O’Beirne’s sister Vivienne Folan said in the aftermath: “My brother Desmond was hard working and larger than life.
“He was on a night out in Trafalgar Square when he was brutally and viciously attacked by two cowards who then calmly walked away and left him for dead.
“As a direct result of this attack he suffered a traumatic brain injury and was left in a vegetative state. Desmond’s life was ended far too soon and our family is left devastated by his loss.”
A spokesperson for Harrods said the pair were not directly employed by the company and were instead employees of Buzz Retail, who provide staff for demonstrations within Harrods, both for less than a year, in 2017.