LAS VEGAS – A few years ago, after another impressive victory by Manny Pacquiao, Top Rank CEO Bob Arum declared that the Filipino superstar was the greatest fighter he'd ever seen.

Given that in his half-century in boxing he'd promoted Muhammad Ali, Sugar Ray Leonard, Marvelous Marvin Hagler, Thomas Hearns, Alexis Arguello, Oscar De La Hoya and even Floyd Mayweather Jr., it was a bold statement.

It only took his trusted matchmaker, Hall of Famer Bruce Trampler, a few seconds to jolt him back to reality.

"He was so excited and so jazzed up and he goes, 'Isn't this guy the greatest you ever saw?' " Trampler said. "And I laughed. I love Manny. He's a great kid and he's had a great, great career. And I said, 'Not only is he not the greatest fighter ever, he's not even the greatest welterweight you promoted.' "

Trampler long has been one of the most astute minds in boxing. But he's more of an old-school type and simply scoffs whenever he hears someone say a current champion could defeat one of the greats from the 1930s, 1940s, 1950s or 1960s.

He raved about boxers like Sandy Saddler, Ruben Olivares, Alexis Arguello, Jose Napoles and Emile Griffith, none of whom received a vote in a Yahoo Sports poll conducted for this story.

"There isn't as much skill in boxing as there used to be," Trampler said. "You know, the manly art of self defense, hit and don't be hit, stuff like that. You don't see that kind of skill much any more. Even a jab, the most basic punch, most kids today don't have one. It's more of a clubbing thing that isn't really that effective."

Mayweather recently made headlines when he told ESPN that he believes he's the greatest fighter ever. Mayweather bills himself as "TBE," which is an acronym for "The Best Ever."

He said he feels he's better than Sugar Ray Robinson, who is widely regarded as the best boxer ever, or Muhammad Ali, who as heavyweight champion in the 1960s dubbed himself, "The Greatest."

Mayweather will meet Pacquiao on Saturday at the MGM Grand in what will be the largest grossing fight in boxing history. While much will be at stake, the position as the sport's best ever won't be, according to a panel of experts convened by Yahoo Sports.

The panel was asked to vote for the 15 men they felt were the greatest of all-time, and there were no restrictions on whom the panel chose. That led to the first Yahoo Sports All-Time Top 25 list.

Those polled were HBO broadcasters Jim Lampley and Max Kellerman; Showtime's Al Bernstein and Steve Farhood; freelance broadcaster and Nevada Boxing Hall of Fame founder Rich Marotta; promoter Lou DiBella; matchmaker Chris Middendorf; Associated Press national columnist Tim Dahlberg; retired AP boxing writer Ed Schuyler Jr.; boxing historian and writer Cliff Rold and myself.

Robinson, not surprisingly, gained 10 of the 11 first-place votes cast and wound up atop the list. He earned 164 of 165 possible points. There were 38 fighters in all who received at least one vote from the panel.

Mayweather wound up 19th and Pacquiao tied for 22nd, which means one of them would likely move up on the list with a win Saturday.

It's hard to imagine either of them, though, moving up high enough to where they'd ever threaten Robinson for the top spot.

Robinson began his career 40-0 and was 128-1-2 at one point. In an Associated Press poll taken in late 1999, Robinson was voted the greatest welterweight and the greatest middleweight of the 20th century.

Trampler relayed a conversation that his mentor, Hall of Fame matchmaker Teddy Brenner, had with the legendary Sugar Ray Leonard when Leonard once asked him if he was as good as Robinson.

"Teddy laughed and told him, 'After you've had another 150 fights, come back and we'll talk,' " Trampler said.

Mayweather made the case for himself in a conversation with Yahoo Sports, when he said that athletes are better today in most sports.

And it's true that athletes are running faster, jumping higher and lifting more weight.

But Middendorf said that's only one aspect of the argument.

"As a baseball and hockey fan as well as a boxing fan, I am always comparing teams and players from earlier eras against the present," Middendorf said. "With all of the sports, the training regimens, sports science and technology have combined to make today's athletes better. So in some way, Manny and Floyd may be better than guys higher on [my] list. But boxing careers are handled so much differently now that you have to give weight to certain fighters of the past for the years of high levels of fights, for fighters who fought matches against opponents with vastly greater weight differentials.

"That being said, it is also easier to judge a team or an individual champion when you have their whole career to consider."

Saturday's bout will be the defining bout for each man. Al Mitchell, who coached Mayweather on the 1996 U.S. Olympic team and has become a quality professional trainer, raved about Mayweather's ability.

He said he thought Mayweather was good enough to wind up in the all-time Top 10 when his career ended, but didn't think he'd make it to No. 1.

But Mitchell said a win over Pacquiao will prove Mayweather is the best of this era and that's all that is significant.

"I've always said, it's just about impossible to say who the best boxer ever really is," Mitchell said. "But you can say who was the best boxer of their era. You have to compare them against those who were competing in their era. Joe Louis was the best in his era. Muhammad Ali was the best in his era. Roy Jones was the best in his era.

"There is no question that Floyd is the best in his era. It's so hard to go back and say, 'Oh, he'd beat this guy or that guy,' because they fought at different times. You can judge the competition they had relative to their era, and Mayweather has had a lot of A-1 competition in his time."

Neither Mayweather nor Pacquiao compares to Sugar Ray Robinson, whose 108 wins by knockout are more than the total victories of Mayweather (47) and Pacquiao (57) combined.

No one else did either, however.

At the end of the day, the winner of Saturday's fight will be the unquestioned best in this era.

As Mitchell said, "That's what it's all about."

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