Black teenager Stephen Lawrence was stabbed to death when a gang of white men "swallowed" him up while shouting racist abuse, a jury at the Old Bailey has heard.
The 18-year-old student was stabbed twice and bled to death after the attack, which took place in Eltham, south-east London, in April 1993.
The accused, Gary Dobson, 36, and David Norris, 35, both from south London, were in court on Tuesday for the first day of the trial. Both men deny the murder.
Prosecutor Mark Ellison QC said: "One of the group was heard to say 'What, what n*****?' and at the same time the whole group rushed towards them."
Lawrence's friend, Duwayne Brooks, managed to run off after shouting "Get up and run, Steve", the court heard.
When Ellison began to describe the killing Lawrence's father Neville left the court. The murdered man's mother Doreen and her son Stuart remained to watch the proceedings unfold. They sat close to the accused as the jury of eight men and four women was sworn in.
Ellison said: "Stephen Lawrence did not manage to get away. The group quickly surrounded him. One witness described that he was swallowed up by the weight of numbers and forced to the ground."
"This group had attacked as one," said Ellison. "The stab wounds were inflicted and then they decamped as one."
The jury heard that the basis for the trial would be a grey bomber jacket and a cardigan which were seized from Dobson after the murder.
The prosecution claims that modern technology can extract important DNA evidence from small samples of blood and hair.
Ellison said: "It consists of the finding of textile fibres, blood and hair linked to Stephen Lawrence on clothing seized from the defendants as part of the original investigation in 1993."
According to Sky News the court was told that a bloodstain on the jacket seized from Dobson contained a small bloodstain that was a billion-to-one match to Lawrence's DNA.
Ellison said that the blood had seeped into the jacket's collar, which indicates it had been wet.
Three fibres encased in blood were also found to contain a match to Lawrence's DNA in the exhibit bag which held the jacket, Ellison said.
The jury was told that 16 fibres were found on the jacket, or the bag that held it, which could have come from Lawrence's clothing.
They were also shown pictures of a pair of blue jeans and a blue sweatshirt taken from Norris's home.
The evidence came to light, the prosecution said, as a result of a 2007 cold case review.
Gary Dobson's defence lawyer Tim Roberts QC made some opening remarks, in which he said his client was "an innocent man".
He added that Dobson was "at home all night with his parents" on the night of the murder and that the forensic evidence offered by the prosecution "was contaminated".
The evidence gathered by police could fit on a teaspoon, Roberts argued, and added that even then it would be difficult to see.
Speaking for Norris, Stephen Batten QC said he agreed with Roberts' concerns about the contamination of evidence.