Freddie Roach has hit out at Floyd Mayweather Jr's lack of respect, while claiming the undefeated welterweight's decision to train with his father will benefit Manny Pacquiao when the pair meet in May.
The fight between five-weight champion Mayweather and eight-weight strap holder Pacquiao has been hotly anticipated for years and the world will finally see the pair face off this year in Las Vegas.
Roach has already claimed that Mayweather's camp are paying fighters to refuse sparring sessions with the Filipino.
And Pacquiao's long-time trainer has called on his man to inflict a first defeat on Mayweather in order to teach him a lesson.
"Floyd is so disrespectful," Roach said. "Manny is the perfect role model for this fight and Mayweather is not.
"I told Manny we've got to beat him for the whole world. There's no way we can't win this fight.
"Floyd's legs don't move like they once did. He's very clever but the fight is so big he may feel like he has to take a risk and exchange with us.
"If he does that, that's the best thing in the world for Manny in my mind. Manny will be performing a public service for boxing when he beats Floyd."
Roach also took aim at his counterpart, Floyd Mayweather Sr, who will train his son for the bout - something Pacquiao's corner man believes will be to their advantage.
"Going against Floyd Sr is a little disappointing," Roach added.
"He just isn't very good, especially during the fight itself. One of our advantages is having him in the other corner."
Mayweather Jr and Pacquiao will come face to face at a media conference next week.