A man collapsed in front of dozens onlookers during a football match in Brockwell Park on Sunday.
Paramedics raced to the scene after the man, age unknown, suddenly collapsed in the middle of the game.
He was given CPR until medics arrived and rushed him to hospital.
A London Ambulance Service spokesperson said: “We were called at 12:31pm on August 2 to reports of a person in cardiac arrest in Brockwell Park, SE24.
“We sent an ambulance crew, an incident response officer, an advanced paramedic and three medics in fast response cars to the scene.
“We treated a man at the scene and took him to hospital.”