Manny Pacquiao's willingness to 55-45 financial split puts onus squarely on Floyd Mayweather Jr.

The burden, finally, is fully and entirely on Floyd Mayweather Jr. to make a fight with Manny Pacquiao.

Pacquiao agreed Thursday during appearances on two separate television shows on ESPN to give Mayweather a 55-45 advantage on a financial split should they fight, as the public has been demanding since late 2009. A match between them is expected to be the most lucrative bout in boxing history.

Pacquiao, who meets Juan Manuel Marquez for a fourth time on Dec. 8 in Las Vegas, had been demanding a 50-50 split. Without such a split, he’d said repeatedly over the last 18 months that he would not agree to a fight with Mayweather.

The other major hurdle blocking the fight between the two men regarded by many as the two best in the world was Mayweather's demand for Olympic-style drug testing. Initially, Pacquiao balked at the testing. He has since changed his stance and has said repeatedly over the last year he would fully comply with the tests, just as Shane Mosley, Victor Ortiz and Miguel Cotto have done in Mayweather's last three fights.

In a telephone interview with Yahoo! Sports on Monday, Pacquiao made no mention of a purse split, but he was as optimistic about the possibility of a fight with Mayweather as he had ever been.

"I think Mayweather will be next," Pacquiao said, declining to specify why.

But by agreeing to give Mayweather the lion's share of the purse, Pacquiao has shifted the onus to Mayweather.

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If Mayweather raises new objections, then it becomes obvious he's not serious and is playing some sort of game.

But at this stage, with the demand for the bout seemingly waning a bit because of all the inaction and drama that has surrounded the talks, it would be a miscalculation for Mayweather to add more conditions.

Mayweather is very much aware of his place in history and wants the fight badly because he doesn't feel as if he's received enough credit for his achievements. He’s 43-0 with 26 knockouts. He won a bronze medal at the 1996 Olympics, though his loss in the semifinals was an outrageously bad call. As a pro, he's won world titles at 130, 135, 140, 147 and 154 pounds.

He has spoken of being rated the greatest fighter ever, and to do that, he'd have to beat the best opponent of his era. Without question, for Mayweather, that is Pacquiao.

To make the fight, though, Mayweather must also stay out of further legal trouble. He was paroled in August after serving just under two months of a six-month sentence for misdemeanor domestic violence. Part of the sentence was suspended, but he could be required by Las Vegas judge Melissa Saragosa to serve that time if he has another incident with the law.

The Las Vegas Review-Journal reported on Tuesday that police responded to a 911 call on Sept. 9 made by Melissa Brim, who said she had a verbal altercation with the fighter. According to the Review-Journal, police found no signs of physical violence.

Though Mayweather went to jail after pleading guilty to a charge of domestic violence upon Josie Harris, he has had several incidents with Brim in the past. Harris is the mother of three of his children and Brim is the mother of the other.

According to Sports Illustrated columnist Michael McCann, a legal analyst, Mayweather could have his parole revoked as a result of the alleged Sept. 9 incident.

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Avoiding such incidents is part of Mayweather's responsibility, both as a man and as an athlete who wants to complete a complex, high-profile negotiation.

Since he was paroled on Aug. 3, Mayweather has kept a low-profile and rarely spoken to the media.

His manager, Leonard Ellerbe, told Yahoo! Sports that he has not spoken "one word about boxing with him," and that he wasn't sure if or when he would.

Pacquiao, though, has to get past Marquez on Dec. 8 to do his part to be available for the fight. They've fought three times in the past, with Pacquiao winning the last two after they fought to a draw the first time.

Many observers feel Marquez deserved to win at least one of those fights, if not all three. Yahoo! Sports scored all three fights in Marquez's favor.

Pacquiao said he is going to go for a knockout to end any controversy that exists. But speaking to Yahoo! Sports Thursday by telephone from Bristol, Conn., Marquez said the issue in his mind was the makeup of the judging panel.

In their first fight, in 2004, Pacquiao knocked Marquez down three times in the first round, but Marquez came back to control the majority of the fight. It was ruled a split draw, with all three judges scoring it differently. John Stewart had it 115-110 for Pacquiao. Guy Jutras had it 115-110 for Marquez. Burt Clements had it 113-113.

Clements was the only one of those judges from Nevada. In their second fight, on March 15, 2008, in Las Vegas, two of the three judges were from Las Vegas. For the last bout, on Nov. 12, 2011, all three judges (Dave Moretti, Robert Hoyle and Glenn Trowbridge) were all from Las Vegas.

Marquez would prefer no Nevada judges for the Dec. 8 match.

"The only other time I had this kind of problem, where the judges didn't do their job, was when I fought [Chris John] in Indonesia [in 2006]," Marquez said. "They didn't do their jobs. The only other time that happened was in Nevada. For me, the best way to have it is to have one judge from Mexico, one Filipino and one from anywhere else but Nevada. I don't care where."

If Pacquiao does his job and defeats Marquez on Dec. 8, then the fate of a potential Mayweather-Pacquiao fight will rest solely on Mayweather's shoulders.

It may be the defining moment of his life.

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