Friends Jennifer Goodhand and Wendy Hislop were walking through a cut way on Station Road when they found Tawana Choruma on the ground.
The 19-year-old was “gasping” and struggling to breathe, a jury at Southampton Crown Court was told.
A recorded interview of Ms Hislop was shown to the court on the second day of the trial against Dominic Adeyemi, 18, who is accused of murdering Choruma on December 18 last year.
Ms Hislop told a detective constable of the unfolding incident the next day.
A “tall, white man” was seen standing over the body of Mr Choruma, with Wendy adding: “The man was trying to kick him into action, telling him to ‘get up’.
“He obviously gave up on trying to get the man back on his feet, and he said, ‘he needs help, get an ambulance’.
“He then ran into the entrance pathway into the recreation ground.
“I saw a large knife lying next to his head.”
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Ms Hislop and former nurse Ms Goodhand sprang into action, checking if Mr Choruma had a pulse and putting him in the recovery position.
This is when their two friends arrived at the scene.
Ms Hislop said: “I did CPR for about ten minutes until the emergency services arrived. It seemed like forever.
“We sensed then the man was dead by this time. We kept doing CPR but it seemed fruitless.
“The medics worked on him for a long time, and when they opened his clothing up, that’s when I saw the stab wound.”
She later added: “It all happened so quickly; we were trying to look after him.
“His face was completely vacant. When we started CPR there were a few gasps and he did groan after that. He didn’t say anything.
“The gasps were the only thing that suggested he might be alive but they stopped not long after we arrived.”
Adeyemi, of Holmes Close, Netley, denies murder.
The trial continues next week.
