The sound when a gloved fist makes contact with a human jaw is quite unlike any other. The grunt of exertion and the involuntary exhalation of pain are immediately noticeable (along with the spray of sweat and blood) when you sit ringside as I have done at York Hall, in Bethnal Green, east London, one of the spiritual homes of boxing.
But over time, you learn to distinguish the distinctive sound of the impact itself, the shot detonating on the temple, cheek, or, preferably for the purposes of inducing coma, the jaw. The jaw is the favoured impact point because it has a higher probability of causing the brain, an organ with the consistency of lightly scrambled egg, to incur trauma and, by implication, create a knockout.
There is another thing you notice, too: The elation among the crowd when the punches start to land. Perhaps elation is the wrong word; it is more similar to euphoria in its primal sense, that led to my being gripped by a fellow spectator during a title fight in 2005. The audience was baying for the next bout before the defeated man had been stretchered from the ring.
Boxing, as even its admirers must concede, is constructed upon violence. Fans thrill to it, in part, for this reason, and the dangers are manifest, most recently exemplified by Nick Blackwell being raced to hospital on Sunday after being stopped by Chris Eubank Jr in a middleweight title bout. A succession of blows had caused a bleed to the brain. As of writing, Blackwell was still in an induced coma.
But what do these observations imply? Let me pin my colours to the mast straight away when it comes to the question of prohibition. This response, often called for by the medical lobby, is, to my mind, both wrong and illiberal. What two consenting adults get up to in the ring is no business of the law.
And yet there remains the more personal question; the question of whether to subsidise this sport through the turnstiles, or by purchasing pay per view, creating a market where young men and women can end up risking brain damage, and potentially worse, for the purposes of mass entertainment.
If you purposefully strike another person you are, by implication, seeking to harm them. The trope that boxers wish merely to whack opponents but not damage them is pure intellectual evasion.
This argument is not merely one of risk. There has been a succession of grim stories in sport in recent weeks, not least the Belgian cyclist Daan Myngheer who had a fatal heart attack at the Criterium International; fellow cyclist Antoine Demoitie killed after a collision with a motorbike; Fernando Alonso crashing into a wall during the Australian Grand Prix (he escaped without injury), and the concussion suffered by Dylan Hartley, the England rugby union captain.
But boxing has a dimension that none of these other sports shares. The objective is to wreak damage, and those who claim otherwise jeopardise their credibility. If you purposefully strike another person you are, by implication, seeking to harm them. The trope that boxers wish merely to whack opponents but not damage them is pure intellectual evasion.
Can it be coincidental that a painfully high percentage of the most storied champions left the sport damaged? Muhammad Ali has lived a half-life since retirement, struck down with Parkinson's disease. Sugar Ray Robinson ended up with Alzheimer's, possibly as a consequence of boxing. Harry Greb, rated as the finest of all middleweights, died penniless and half blind at the age of 32.
A seminal 1983 article in Sports Illustrated entitled Too Many Punches, Too Little Concern, cited CT scans on eight former champions, with five displaying brain abnormalities. There is no known cure for chronic traumatic encephalopathy, the umbrella condition that encompasses the familiar curse of the ex-professional boxer - punch drunken-ness.
We should note, too, that while boxing gyms help youngsters to develop character, there are dozens of character-forming activities that don't involve hitting another person in the head. Let me say, loud and clear, that boxing is a sport with a rich cultural heritage and has produced a succession of iconic figures who, particularly in the form of Ali and Joe Louis, changed the world for the better. Its protagonists are skilled, courageous and when they collide in the ring, create a unique form of beauty, what A.J. Liebling called the "science of sweet bruising". I have been in thrall to it for most of my life.
But I cannot help wondering if it is, to use the expression of Hugh McIlvanney, one of its finest chroniclers, "worth the candle". "Quite a few of us who have been involved with it most of our lives share the doubts," he wrote after the death of Johnny Owen, the Welsh bantamweight who was knocked out in 1980, never regained consciousness and died two months later.
My doubts, like those of so many others, have never been more insistent.
THE TIMES, LONDON