‘We call it sparring,’ I said, ‘not fighting.’

‘But it’s full contact, right?’ he said. ‘You’re trying to punch each other’s lights out, right?’

I shrugged. ‘Of course.’

I saw no point explaining that there was an etiquette involved in sparring, an unwritten and unspoken code of honour, and a deep degree of trust. He didn’t look as though he would be very interested in any of that stuff. I had been sparring with Fred for five years, but neither of us had ever been hit with a low blow, neither of us had ever left the ring feeling angry. Our friendship had been forged in the rough intimacy of sparring. But it was true what the weightlifter said: when we sparred, we didn’t hold anything back.

‘You sucker-punched me,’ the weightlifter said, the anger flaring.

‘You were rude to my dog.’

‘I wasn’t ready then. But I’m ready now.’

‘I just did three rounds,’ I said.

‘I want to see how tough you really are,’ he said. ‘Unless you’re chicken.’

I was looking at his yellow gloves – a pair of ten-ounce Cleto Reyes gloves, the best boxing gloves in the world, handmade in Mexico, but far too light for hard sparring. But that wasn’t what bothered me.

‘I’m not sparring with you,’ I said, taking my gloves off.

When I moved to get out of the ring, he blocked my path.

‘Why not?’

‘Because you don’t have a mouthguard.’

‘I don’t need a mouthguard.’

‘Yes you do,’ I said. ‘Everybody needs a mouthguard. Because I could catch you with my elbow. Or I could bang you with my forehead. And there’s even an outside chance that I might actually punch you in the mouth.’

Then Fred was there. He took the weightlifter by the elbow and easily turned the far bigger man around. Fred had worked the doors at some point.

‘See that sign?’

On the walls of Smithfield ABC gym there were framed photographs of boxers. They were a certain kind of boxer – natural-born fighters, all grit and glory, the kind of boxers Fred loved. Jack Dempsey. Jake La Motta. Joe Frazier. Marvin Hagler. The hard men of the sport. And there were other framed photographs – pictures of kids boxing in Cuba, a dozen of them in the ring at a time, shirtless and skinny and sparring with gloves that looked as though they had just been dug up. And above them all there was a sign.

NO SPARRING WITHOUT PERMISSION

‘You don’t have permission,’ Fred said.

Fred was the smallest man in the gym. But in that place of assorted hard nuts – where policemen came to keep fit, and rough boys from sink estates came to learn the sweet science of bruising, and young women came to learn self-defence, and white-collar City types came to push themselves to the limit – nobody argued with him.

The weightlifter got out of the ring.