What was the big deal at Las Vegas on Saturday night?

Boxer Floyd Mayweather Jr. beat Manny Pacquiao for the welterweight world championship with a unanimous decision in what is considered the highest-grossing bout in boxing history. 

Mayweather and Pacquiao are regarded as the two best fighters, perhaps in any weight class, of the past decade. Mayweather, 38, is an American with a baby face and an unblemished professional boxing record (48 wins, including last night's, and no losses). Pacquiao (pronounced PAK-ee-ow), 36, is a mop-haired scrapper and Congressman with presidential ambitions from the Philippines. He has 57 wins to his credit, 6 losses and 2 draws.

But tangled in boxing's familiar knot of egos, contracts and self-preservation, a head-to-head bout looked unlikely as the ageing boxers moved towards retirement. A chance face-to-face meeting between Mayweather and Pacquiao at a Miami Heat game in January prompted negotiations that led to the match.

What is welterweight and can anyone actually wear the belt Mayweather was holding aloft?

Welterweight means the boxers must weigh more than 140 pounds (63.5kg) but no more than 147 pounds (66.5kg).

The world of boxing has an overstuffed alphabet soup of competing controlling bodies (WBC, WBO, WBC, IBF). Each gives belts to each of its champions in each of the weight classes. They are called belts, though they are too big and heavy to thread through the loops on anyone's pants or even to serve as superbelt-like cummerbunds.

So, how much money did Mayweather take home?

The purse, the majority of it from pay-per-view revenue from several million American households paying about $90 each to watch, was estimated at $300 million. The contract called for Mayweather (nicknamed Money) to receive 60 per cent, win or lose.

Mayweather, asked to confirm if he received a $100-million cheque after the fight, pulled it from a pocket. "The cheque got nine figures on it, baby," said Mayweather, whose payday could double as the revenues get tallied.

What about celebrities?

In the audience there was, to be sure, the most exotic constellation of luminaries ever assembled outside the Oscars red carpet.

There were some conspicuous absentees, however, not least CNN reporter Rachel Nichols and ESPN's Michelle Beadle, who allegedly had their fight credentials revoked for daring to refer to Mayweather's history of domestic violence.

Isn't the winner very popular?

Doesn't look like it. The catcalls and boos did not take long to rain down on Mayweather. "The most tragic thing in the world," wrote George Bernard Shaw, "is the man of genius who is not a man of honour." That label fits Mayweather rather neatly.

A dark past, which encompasses seven claims of physical assault against five different women and a jail term, is central to the sense of alienation that many feel from Mayweather.

The coldness of Mayweather's victory speech, in which he reserved particular thanks for his watchmakers Hublot, did not exactly burnish his image.

He gave every indication that his distinction as the richest athlete on the planet mattered much more to him than being unbeaten for his entire career.

OK, how good was the fight?

A good one, if you are among the aficionados.

A peerlessly accurate fighter, Mayweather proved by the surgical dismantling of Pacquiao that there was no boxer alive better at calculating and punishing an adversary's weaknesses.

Mayweather looked indestructible at times. Pacquiao carried momentum through the early rounds with his robust, forward-moving attack, sometimes smiling at Mayweather. When the bell sounded, the judges ruled that Mayweather actually had led handily throughout.

Is Mayweather the greatest fighter of all time?

Laila Ali, daughter of Muhammad, offered an especially withering assessment. Mayweather was vocal throughout fight week in arguing that he was the finest boxer of all time, greater even than Ali, but Laila, a retired and undefeated fighter who trained under the guidance of Mayweather's father and uncle, claimed that he was a "broken person". She told CBS: "When you have money and you have power, you don't have somebody to pull you aside and give it to you straight. I dislike the way that he treats people, and I'm definitely not down with this beating up on women. That's very cowardly."

Will this fight help revive the glory days of boxing, the so-called sweet science?

"It is a huge economic event," said Thomas Hauser, a boxing columnist and the author of Muhammad Ali: His Life And Times. "But for the business of boxing, it doesn't mean anything other than a small group of people counting a large amount of money - and then we'll go back to business as usual."

The epitaph for a sport that once commanded the front pages of newspapers and minted heroes and antiheroes - from Jack Dempsey and Rocky Marciano to Ali and Mike Tyson - has been written in larger and larger type over the past decades.

Many recognise the sport's fundamental problem: it is too brutal for all but a few.

There are other problems, too, including boxing's multiple (and dubious) sanctioning organisations, the track record of corruption within its management ranks and a business model that puts the sport's premier events behind an expensive pay wall.

But others believe "Saturday night is a good idea. You can build personalities and an audience there".

No one is ready to declare boxing resurrected, but some agree that a series of million-dollar days is better for the long-term health of the sport than one billion-dollar weekend.

Was it the Fight of the Century after all?

The electricity did crackle inside the MGM Grand Garden Arena as the crowd that had paid Wall Street salaries for the privilege of a ticket seemed scarcely able to believe that these two boxers had been brought together at last.

But the reality did not quite measure up to the concept. Some of Mayweather's defence - sliding away from the Pacquiao bombardment with the deftest feints - was a technician's dream.

As a spectacle for non-aficionados, the audience who had flocked so enthusiastically to this fight, it was deficient.

"We could marvel at the brilliance of Mayweather's evasions, which allowed Pacquiao to connect with just 81 of 429 punches, but we had come in anticipation of a blood-and-thunder slug-fest, not a clinical act of containment," Oliver Brown wrote in The Daily Telegraph, London.

Michael Powell wrote in The New York Times: "Several heads along press row more knowledgeable than mine on boxing noted that this match as it turned out was - perhaps - The Fight of the Last Month. That admittedly makes for a challenging marketing campaign."