Murdered teenager Stephen Lawrence innocently chatted about football with his friend moments before he was stabbed in the street, a court heard on Wednesday.

Hospital worker Royston Westbrook told the Old Bailey that he saw a group of white men collide with Lawrence and Duwayne Brooks and violently attack them, the Press Association reported.

Westbrook re-lived the events of the night that Lawrence died in Eltham, southeast London, in April 1993.

Gary Dobson, 36, and David Norris, 35, both of south London, are on trial for the murder, which they deny.

Westbrook told the court: The two black boys, Stephen and Duwayne, were standing right by the bus stop. They were kicking about, they were talking about football... they were just generally chit-chatting.

The teenagers were discussing whether or not they should wait for a bus or walk back up to a roundabout to try to get another.

In the end they made the fateful decision to walk away, and were set upon by the gang.

They just collided - that's what it looked like, said Westbrook. They were just heading towards each other and that was it.

They grabbed Duwayne Brooks' wrist but he turned his wrist and just pulled away. Duwayne ran towards the bus stop where we were standing and turned round and shouted something like 'Leg it, Steve' or 'Run, Stephen.'

Brooks managed to run away but Mr Lawrence was forced to the ground.

Westbrook told the jury: I saw them surround Stephen and he went down basically through sheer weight of numbers in the middle of them ... it looked at the time that someone went to punch him.

One of the attackers then lifted his leg to try to kick Lawrence.

Westbrook said: He lifted his leg backwards to give him a good kick. As he did that, Stephen came up between his legs, struggled up and ran up the road in the same direction as Duwayne Brooks had gone.

I think that whoever was doing the kicking was aiming to give a good kick so he lifted his leg right up but Stephen saw the opportunity to get out.

The witness, who was on his way home from working at a nearby hospital that night, did not see any weapon and thought the gang had only managed to punch Lawrence.

He said: It was so quick, it really was quick -- it was about 10 seconds -- and my impression going away from that was that they managed to punch him and that was it.

Moments later, while on a bus, he saw the stricken teenager lying on the ground.

The trial continues.