When Argentina face Spain in Sunday's World Cup final, Lionel Messi and Lamine Yamal will meet on a football pitch for the first time. Yet their story — improbable, tender, and almost cinematic — began nearly two decades before either could have imagined it.

In 2007, a 20-year-old Messi had just established himself as a regular starter for Barcelona. Yamal, whose family had won a competition run by Catalan newspaper Sport in partnership with shirt sponsor and international children's charity Unicef, was brought to the away dressing room at Camp Nou to be photographed with a first-team player. By pure chance, the family was paired with Messi.

Yamal was just five months old.

The photograph that stunned the world

Barcelona-based photographer Joan Monfort was behind the lens that day. He captured a grinning Messi cradling and bathing the tiny infant — a baby who would, against all statistical probability, one day become the man most likely to inherit Messi's role on Barcelona's right wing.