Whatever the final sales figures for the Floyd Mayweather-Manny Pacquiao pay-per-view happens to be, it's going to be a long time before another fight approaches it.

Sales are still being totaled and it's not likely that an announcement will be made until the end of the week, at the earliest. Trends, though, are extremely high and it will obliterate the record of 2.48 million. That was set in 2007, when Mayweather defeated Oscar De La Hoya at the MGM Grand.

Buys for Mayweather's victory over Pacquiao on Saturday will soar past 4 million.

It took a perfect set of circumstances for the stage to be set for that type of fight to occur, and though the record will likely be broken in the future, it's going to take a long time.

Boxing promoters and television executives consider the April 19, 1991, bout in Atlantic City, N.J., between Evander Holyfield and "Big" George Foreman as the first pay-per-view bout. There were roughly 15 million addressable homes and the fight sold 1.45 million.

The sales record stood for more than five years, until Holyfield-Mike Tyson I on Nov. 9, 1996. Their rematch, on June 28, 1997, became the new standard with 1.98 million sales.

It was matched by the Tyson-Lennox Lewis fight in 2002, but it wasn't broken again until De La Hoya-Mayweather in 2007. That means the record stood for 10 years.

Once the Mayweather-Pacquiao number is official, that will eclipse a mark that stood for eight years.

How did the Mayweather-Pacquiao fight get so big? It was a unique set of circumstances that came together all at once to create the perfect storm.

The first is the public's long-term familiarity with both fighters. Mayweather fought the vast majority of his career on American television. He won an Olympic bronze medal in 1996 on NBC. He fought on ESPN2 in many of his early pro bouts, and began fighting on HBO in 1998. So he's been on American television for nearly 20 years.

Pacquiao's American debut in 2001 was on HBO and, with the exception of two small pay-per-view shows Top Rank put on, he's been in big fights on American television ever since.

The familiar names and brands that are televised a lot tend to subsequently get the best ratings. It's why the Dallas Cowboys and New York Yankees, for example, are on TV so much and rate so well when they are.

A second major factor was the coverage both fighters got from non-boxing media. Pacquiao was featured in a 2010 segment on "60 Minutes." He appeared on CNN many times. He was on the cover of the international edition of Time magazine.

Mayweather appeared on WWE programming in 2007 after defeating De La Hoya and then competed in WrestleMania. After that, he appeared on ABC's "Dancing with the Stars." Both of those appearances made him a familiar name and face to an entirely new audience.

Third, when Pacquiao knocked Ricky Hatton cold on May 2, 2008, and then battered De La Hoya into retirement in December of that year, it set up a debate for sports fans: Who deserved to be No. 1 in the world in boxing?

Mayweather had long been considered the pound-for-pound king. He'd won a split decision from De La Hoya in 2007 and then stopped Hatton in the 10th round that December.

Pacquiao's passionate fan base began pushing the fact that he'd caught up to or surpassed Mayweather as the world's No. 1 fighter. The fact that they were in the same weight division and each had at least a claim to being the best created a rivalry that drove interest.

Fourth, Pacquiao's extracurricular activities, such as being elected to Congress in the Philippines and cutting a popular record with Dan Hill made him a likeable and familiar face to many non-boxing fans. So, too, did his regular appearances on ABC's Jimmy Kimmel Show.

Finally, there were the long and tortured negotiations to put the fight together. Those began in late 2009, after Pacquiao stopped Miguel Cotto. And though it looked for a long time like they'd never fight, the media covered the story zealously and fans ate it up.

By the time Pacquiao defeated Chris Algieri last year in Macau, China, even non-boxing fans had become aware of the fighters and were calling for them to meet.

Outlets such as The New York Times and CNN that rarely, if ever, cover boxing were out in large numbers, with detailed and extensive coverage.

Sports talk radio stations around the country discussed the fight way more than normal.

For that to happen again, it's going to take two marketable fighters who have a good command of English. Canelo Alvarez, who fights James Kirkland on Saturday in Houston, is one of the game's most popular fighters, but his appeal is limited mostly to hardcore boxing fans.

He hasn't been on free television much and he doesn't speak much English. Plus, there is no real natural rival for him who can be built over time.

He may wind up fighting Cotto for the middleweight title later this year, and while that figures to be a sensational fight, it's not going to get a hundredth of the buildup that Mayweather-Pacquiao did.

Some day, two fighters will come along who will capture the imagination of the public and they'll meet in a hot fight that will do a higher figure than Mayweather-Pacquiao.

That day is a long way away, though.