The best ways to describe the performance Manny Pacquiao delivered against Miguel Cotto in 2009 at the MGM Grand Garden in Las Vegas would be "awe-inspiring" and "jaw-dropping."
At that point, Floyd Mayweather Jr. had been widely considered the best fighter in the world by most neutral experts for at least eight years, perhaps 10.
But after Pacquiao left the ring following his 12th-round stoppage of the great Puerto Rican on Nov. 14, 2009, there was a legitimate question as to whether Mayweather's reign as pound-for-pound king had just ended.
Pacquiao was so fast, so strong, so vicious and so precise in his one-sided win over Cotto that it was easy to forget that Mayweather had just toyed with the legendary Juan Manuel Marquez just two months earlier.
Whether it was Mayweather and Pacquiao, or Pacquiao and Mayweather, there was little disagreement within the boxing community that these were the two finest fighters in the world.
The end of the Pacquiao-Cotto bout signified the beginning of talks to make a Mayweather-Pacquiao fight.
More than five years later and despite hundreds of millions of words having been written and spoken about the topic, the two legends have yet to face each other.
And though there are signs that they're moving toward an agreement for a May 2 bout in Las Vegas, there still is no deal between them.
Without question, neither man is the same as he was in 2009. Mayweather has remained unbeaten, going 7-0 with one knockout since 2010. Pacquiao is 7-2 since 2010, though a large percentage of those who witnessed his loss to Timothy Bradley in 2012 thought Pacquiao deserved the decision.
But Mayweather was hit more by Marcos Maidana in his last two fights in 2014 than he had been in years. It's not a stretch to say the Mayweather of 2007-09 would have waltzed past Maidana with ease and would have left the ring with nary a bump, bruise or scrape.
Mayweather will turn 38 a week from Tuesday and isn't as defensively brilliant as he once was. Oh, he's still a magician and does things in the ring that nobody else can dream of doing, but he's much more hittable than in the past.
It's a similar story with Pacquiao. Even if you set aside his loss to Bradley in 2012 as a judging error, he was still knocked out by Marquez later that year. Now, Pacquiao was on the verge of stopping Marquez when Marquez, perhaps in desperation, fired the counter right that stopped Pacquiao cold.
Despite the apparent regression in the fighters' skills, though, public interest in seeing Mayweather and Pacquiao fight remains at a fever pitch.
The will-they or won't-they speculation in the media never seems to cease. Everyone who has a computer and a blog seemingly has a source who has told them that, take your pick, the fight would be announced Christmas week, on New Year's Day, on Martin Luther King Day, at the Super Bowl, at the NBA All-Star Game and now on Mayweather's 38th birthday on Feb. 24.
Despite the on-again, off-again nature of the talks, despite the rhetoric, despite all the nonsense that has happened between them, interest in the fight has only increased over the years.
Bovada, an online sports book, set an over-under on how many pay-per-views a Mayweather-Pacquiao fight would sell at 3.15 million. Right now, under is minus-160, while over is plus-120. The record is 2.5 million, set in 2007 when Mayweather defeated Oscar De La Hoya.
Part of the interest in the fight has no doubt to do with the style matchup. Mayweather is the master boxer of this generation, at his best, an almost impregnable foe. He's able to see punches coming from virtually any angle and not only is able to avoid them, but land stinging counters in return.
Pacquiao is the left-handed slugger, the likes of which Mayweather hasn't faced. If Mayweather has struggled in his career while reeling off 47 wins in 47 fights – and we use the word “struggle” loosely – it's been against left-handers.
At his best, Pacquiao is a fast, powerful and devastating puncher who leaves a trail of elite fighters in his wake. Maidana showed in his two fights with Mayweather that pressure can work against the pound-for-pound king.
No one with any credibility would seriously try to suggest that Maidana is more capable of applying effective pressure than Pacquiao.
So, the interest in the fight may stem from the perfect matchup of styles and time. Like Muhammad Ali and Joe Frazier in 1971, it's a pairing of boxer vs. slugger. And like Ali-Frazier I, it pits two men perceived by the public to be the two best in their division, as well as in the world.
Even though both are perceived to have declined, most sites that do such things rank them Nos. 1-2 pound-for-pound. The Ring has Mayweather No. 1 and Pacquiao No. 3; ESPN.com has them 1-2, with Mayweather receiving all 10 first-place votes in its poll and Pacquiao receiving nine of the 10 second-place votes.
And so, despite whatever decline there may have been in their ability, they remain the two best fighters. Their styles seem to mesh in order to give a sensational fight.
The bout also has historic implications. Mayweather has two more fights left on his deal with Showtime, and he's said he'll retire when it's done. Even if he fights on after the deal’s expiration, a match with Pacquiao seems like the last – and best – chance for someone to defeat him.
If Mayweather handles Pacquiao easily, then it's likely he'll finish his career unbeaten.
So, while it seems that logic would dictate that the public would have tired of the five years of tortured "will it or won't it happen" talk, such is not the case.
If it's done – perhaps when it's done – it's going to be as big of an event as boxing has ever seen.