A teenager accused of killing schoolboy Kodjo Yenga has told the Old Bailey it was the victim who started the fight and he only took part to save face.
Kodjo died from a single stab wound to the heart
Kodjo, 16, died from a single stab wound to the heart after being attacked in Hammersmith Grove, west London, in March last year.
The accused, who is now 15 but was 14 at the time, told the court he also did not expect others to join in.
He is one of six boys, aged between 14 and 17, who deny murdering Kodjo.
The boys cannot be named because of their age.
The Old Bailey has heard that Kodjo was chased by a gang of youths shouting "kill him" before he was stabbed in the heart.
On Wednesday, the teenager told jurors that he had heard from friends that Kodjo wanted to beat him up.
He said when they bumped into each other they arranged to fight but that he only did it because his friends, including four girls, were there.
"He was bigger than me but I went along with it. I didn't want to lose face in front of other people," he said.
"He threw a punch at me which connected with my face. It was a hard punch. I hit him back by punching him in his face."
The boy said he started chasing after Kodjo, and his friends joined in, even though he himself was expecting it to be a one-on-one fight and had not asked them to help.
He told the jury that he saw one of the other boys had a rounders bat but did not see anyone holding a knife.
He also said Kodjo was being chased by a dog.
The teenager told a jury that later he was standing behind others involved in the fight when he heard shouts of "stop" and that the police were on their way.
As he ran off another boy shouted "the boy's dropped" and he thought that meant Kodjo had fallen, he said.
He ended up at his grandfather's house and moments later he allowed in another of the boys, whose shirt was covered in blood.
"He was in a panic and was telling me to close the door because the police were coming," he told the court.
"I told him to get out of the house because I could hear sirens," he said.
The trial was adjourned until Thursday.