Those who hold the title of world heavyweight boxing champion could argue that they have in their hands the biggest individual prize in sport, including the now 56-year-old Mike Tyson.
But then there are those who are the true greats among the long list of belt-holders, so here we take a look at some of the best fighters to have held the honour.
Louis and Marciano leave massive marks
John L Sullivan became the first recognised world heavyweight champion after originally being a bare-knuckled fighter in 1882, and while fighters such as Jim Jeffries, Jack Dempsey and the first black fighter to hold the title, Jack Johnson, were stars before the end of the 1920s, the first who could lay a claim to be the best ever is probably Joe Louis.
The Brown Bomber made 25 defences of the title he won in 1937, which is the most ever achieved by any boxer in any division, while no-one has held the heavyweight title for longer than his 11 years and ten months.
Louis' most famous fight was his rematch against Max Schmeling in 1938 at Yankee Stadium, which he won inside a round in a bout that proved a massive blow for the German propaganda machine.
That Louis, who grew up in humble circumstances in Alabama and became a true hero for black Americans, earned such records merits his inclusion and one of the three fighters who beat him in his 69 professional contest, Rocky Marciano, has to be included too.
Louis was well past his prime when Marciano defeated him at Madison Square Garden in 1951, but the Rock from Brockton won all 49 of his professional fights, 43 inside the distance and is the only heavy champion to have been undefeated, which means he has to come into the equation.
The golden heavyweight era
The start of the real golden age for heavyweight boxing was probably on 25th February 1964 when a 22-year-old from Louisville called Cassius Clay beat Sonny Liston in a huge upset in Miami Beach.
Clay would soon become Muhammad Ali and is almost universally acknowledged as the greatest sporting icon of the 20th century.
Ali's fight record really doesn't tell the whole story and it could be argued that his best boxing years were spent serving a three-year ban after he refused to be conscripted to serve in the Vietnam War.
And after regaining his licence in 1970, he was beaten by a unanimous decision by another great champion, Joe Frazier, in what was dubbed the Fight of the Century at Madison Square Garden after Frazier had floored Ali in the final round.
Frazier would go on to hold the title until January 1973 when his 29-0 record was tarnished by a performance of destruction from George Foreman, who battered the champion, knocking him down six times before the fight in Kingston, Jamaica was stopped inside the second round.
All three dominated the scene in the 1970s and all can be considered among the cream of the crop.
Bouts such as the Rumble in the Jungle, when Ali allowed Foreman to punch himself out before dramatically downing him in the eighth round, and the Thrilla in Manilla - when Ali and Frazier slugged it on in 100F heat in the Philippines - will go down as some of the greatest sporting occasions in history.
All three men were among the greatest heavyweights to have ever laced a glove, and Foreman, who retired in 1977, came back and won a world title at the age of 45 when he beat Michael Moorer in 1994
The next generation
Boxing would never hold the same captivation for the sporting public, but Larry Holmes, who was Ali's former sparring partner and who beat The Greatest in his penultimate fight in 1980, deserves a strong mention.
Holmes won his first 48 fights, but was unable to match Marciano's record when he was surprisingly beaten by Michael Spinks in 1985.
His record was perhaps tarnished by several comebacks, one of which came against the undoubted star of the 1980s, Mike Tyson.
The New Yorker announced himself on the scene unlike probably any other sportsman, as his overtly aggressive style gave the impression he was simply unbeatable.
He was just 20 when he won the world title against Trevor Berbick, who wobbled all over the ring after being battered in the second round of their meeting in Las Vegas and Tyson seemed destined for a decade at the top of the game.
More destructive performances followed, including a 91-second demolition of Spinks, but he then suffered one of sport's greatest ever shocks when he fell to James Buster Douglas in Tokyo in 1990.
Tyson was forced to take time away from the ring for three years and, while he was always great box office afterwards, it was more to do with the controversy he attracted than his ability.
But the raw power he demonstrated in the early years of his career, he has to be considered among the game's greats.
And it would also be a disservice not to mention one of the men who beat him, Lennox Lewis, in this company.
Lewis became the first British heavyweight world champion of the 20th century in 1992 and made three successful defences, including one against Frank Bruno, before he suffered a shock defeat to Oliver McCall.
But after regaining his title, the fact he beat Tyson and Evander Holyfield - following a controversial draw in which many commentators argued his opponent was extremely fortunate - it could be argued he deserves consideration among a strong field to be one of the greatest ever heavyweights.
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