Floyd Mayweather
Boxing champion Floyd Mayweather Jr smiles as he greets fans and amateur boxers during a visit to conduct training clinics in Soweto [Reuters/SIPHIWE SIBEKO] Reuters

Top-Rank promoter Bob Arum said reigning pound-for-pound boxing champ Floyd Mayweather Jr. has flaws in his fighting style, believing the Grand Rapids native is just scared to face a left-handed power puncher like Pacquiao.

In his recent interview on ESPN, Arum shared his opinion as to why Mayweather continues to dismiss Pacquiao as his opponent in the ring. The veteran promoter believed Mayweather doesn't like to take on left-handed fighter as his shoulder roll defense is vulnerable against southpaw fighters.

"Don't you understand why the Mayweather-Pacquiao fight won't and can't happen?" Arum said to ESPN. "I promoted Mayweather for over 10 years. One thing I learned over those years is that Mayweather doesn't like or won't fight southpaws," Arum stressed.

"Why? Because his whole style is geared for a right-handed fighter. And to compound that if the southpaw is really fast and moves, that would give Mayweather and his style a lot of problems, and it would really jeopardize Mayweather's record of an undefeated fighter," he added.

Arum even compared Mayweather to German World War II leader Adolf Hitler, as he believed the pound-for-pound boxer is becoming a dictator in fight negotiations.

"That's why the fight isn't happening. Because this is almost like before the 2nd World war. Hitler wanted this and wanted that, and if we gave him this peace would occur. But it was never enough, because Hitler's dream was to go to war and conquer all of the world. Now Mayweather's dream is to stay undefeated; so whatever you give him, if Manny agreed to fight for nothing, it wouldn't be enough. Don't you understand that?," Arum said.

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Pacquiao called out again Mayweather to arrange a showdown with him in his latest appearance on ESPN's Keith Olbermann's ESPN show.

"I want that fight [with Mayweather] but it's up to him," Pacquiao said. "What I can say now is that our line is open 24 hours, seven days a week. If he will call and say 'yes' then the fight [will happen]," Pacquiao told Olbermann.

Pacquiao is fighting Timothy Bradley for the WBO Welterweight title on April 12 at MGM Grand Garden in Las Vegas, Nevada while Mayweather is expected to pick his next opponent (either Amir Khan or Marcos Maidana) next week.

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