The final moments of Asif Kapadia’s magnificent film Diego Maradona are almost too painful to watch. To a soundtrack of an interview conducted when he was at the peak of his powers in Napoli, when he talks of the football pitch being a refuge, a sanctuary, a place of freedom where he could express himself without fear, we see Maradona in his late fifties attempting to play five-a-side with his friends. The juxtaposition of the glorious athlete of our collective memory and the hobbling, pot-bellied, arthritic shadow he became is a telling reflection of his decline. So precipitous was his fall, it almost appeared to be the consequence of a Faustian pact, an agreement to become the most influential footballer in the world in exchange for a sporting afterlife of misery and self-loathing. The sadness is that any evaluation of his genius cannot but take account of what happened next. It had been long coming, but we were given first indication of his unravelling at the 1994 World Cup. The man who had dragged his country to victory in 1986, then almost repeated the trick in 1990, was by now a drug-addled parody of his glory days. His goggle-eyed celebration when he scored his last ever goal for his country in the game against Greece was a symptom of his personal nightmare: the man was wired beyond repair. Banned, traduced and shamed, his playing career was over. But back in his homeland he was still revered. And no wonder, given what he had delivered. He parlayed his celebrity into a lucrative turn as a chat show host, before his inability to control his appetites compromised his facility to frame a question. Still, he knew about football, so in 2005 he was offered a role as sporting director at Boca Juniors, his old club in Buenos Aires’s most roughhouse neighbourhood. In a stadium that, 25 years after he last kicked a ball there, remains a shrine to his brilliance, his very presence was an inspiration; Boca won four trophies in two seasons with him watching enthusiastically from his private box. In a manner that was to become a pattern, though, it did not last. He fell out with the club president and was gone.