Floyd Mayweather Sr insists Manny Pacquiao will be forever haunted by the savage knockout suffered at the fists of Juan Manuel Marquez.
Pacquiao was rendered unconscious in the sixth round by a devastating straight right hand from Marquez in 2012 with the disturbing end to his fourth clash with the Mexican plunging his future into doubt.
Subsequent victories over Brandon Rios, Tim Bradley and Chris Algieri were enough to revive the prospect of facing Floyd Mayweather with the rivals finally colliding at the MGM Grand in the early hours of Sunday morning.
But Mayweather Sr, who returned to his son's corner in 2013 following a 13-year estrangement, believes Marquez has left the Filipino southpaw's career on borrowed time.
"Once you get hit like he did by Marquez and your ass goes to sleep, it won't take too many more punches before it happens again. He's gone," Mayweather Sr said.
"Anyone who has been in boxing long enough knows what I'm talking about. I don't know what round it will happen in, but when he gets hit like that again, it will happen again. Simple."
Mayweather Sr was typically eccentric as he addressed the media two days out from the Las Vegas superfight which is expected to generate a record-breaking £332million, rubbishing one question as "weird, crazy, dumb and stupid".
When asked which of Pacquiao's 57 wins was his best performance, he replied: "When he got stretched out by Marquez."
A minor dispute is brewing with Pacquiao's trainer Freddie Roach asking why the Mayweather camp have missed the deadline to submit their boxer's fight gloves to the Nevada State Athletic Commission.
The Cleto Reyes worn by Pacquiao have been given the all-clear but Roach is concerned that he has yet to examine the gloves Mayweather will be wearing. Mayweather Sr gave a theatrical response.
"Scary! I don't think the gloves are an issue because Manny can put on the same kind of gloves that Floyd will be wearing. That ain't nothing but fear," he said.
"Freddie Roach the joke-coach-Roach. I keep telling you. Freddie has been saying for years that we're scared of Manny. Now you'll see.
"To be honest with you, I don't think it's going to be much of a fight. The fight is already won. Trust me.
"They keep talking about how scared Floyd is and how scared he has been for the last five years, but they're scared. Floyd would whoop Manny any time of any day of any year."
Pacquiao's corner can be chaotic in between rounds with Roach admitting the emotion of the Filipino's assistants often proves difficult to keep in check.
"Buboy (Fernandez, Pacquiao's second) is supposed to repeat what I say in Philippine," said Roach.
"But I'm not sure that's what happens sometimes, because he talks a lot longer than I do.
"When Manny was fighting Miguel Cotto, he was getting hit on the ropes and Buboy started crying.
"I was thinking: 'I've got one guy doing what I told him not to do and another guy crying.' It does get a little funny sometimes."
Meanwhile, Mayweather has been warned by one of his predecessors as pound for pound king that he faces a sustained barrage of punches from Manny Pacquiao.
Roy Jones Jr, a former four-weight world champion, believes Pacquiao's speed and work rate will trouble Mayweather.
"Manny's best game plan is pressure, pressure. Floyd has never fought an opponent like Manny who throws so many punches, has power in both hands and is southpaw," Jones said.
"If you look back to Zab Judah, he is the closest to that and he gave Floyd a good run in the first four rounds. After that he started to decline.
"Everyone knows that's Zab's MO, he declines after four rounds. But Manny doesn't decline after four rounds, he goes higher.
"Guys have tried to pressurise Floyd, but no-one has pressurised him like Pacquiao will. Of course Manny can be reckless and that's what Floyd will be planning on.
"We know that Manny has to be aggressive and Floyd's planning for him to be aggressive. Is Floyd going to master aggression with aggression, or is he going to use tactical boxing?
"He can do either. Manny can do one thing, Floyd can do two. Floyd can be aggressive or he can be tactical. It's going to be a very good fight and I'm not sure who is going to win."
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