Timothy Bradley's camp continues to throw barbs to Manny Pacquiao ahead of their upcoming rematch on April 12 at the MGM Grand in Las Vegas, Nevada.

Bradley's trainer, Joel Diaz, told BoxingScene that Pacquiao's storied career is nearing its end, saying that he is convinced Pacquiao will not be the same fighter that he was before.

Pacquiao is coming off a convincing unanimous decision win over Brandon Rios in November, but Diaz pointed out that he failed to prove that he was the same fighter who manhandled Oscar Dela Hoya, Miguel Cotto, Ricky Hatton, Erik Morales, and Marco Antonio Barrera before.

Diaz echoed Bradley's statement, saying that the former pound-for-pound king has lost his killer instinct after absorbing a sixth-round knockout loss to Juan Manuel Marquez in December 2012.

"A lot of people are saying that Pacquiao is still bringing what took him to the top, but for me - Juan Manuel Marquez left his mark on him, with this knockout, it affected him," Diaz said.

The 35-year-old Filipino boxing icon was previously indestructible as proven by his eight titles in as many divisions, but Diaz insisted that Pacquiao has already lost that aura.

"Manny Pacquiao was indestructible and he already lost that aura," Diaz said. "I do not have doubt that at the age of 36, already with 60 fights, 60 wars, and 60 preparations, the body is suffering from the work, the punishment, and there has to come the moment where you think about saying goodbye."

Diaz added that Pacquiao is already following the footsteps of former boxing greats, who looked unbeatable during the prime of their careers, but suffered devastating defeats.

Diaz cited Mexican boxing legend Julio Cesar Chavez Sr., whose career went on a downward spiral after absorbing a knockout loss to Oscar Dela Hoya in June 1996.

Chavez Sr. lost to Dela Hoya again in their rematch in 1998, which was followed by defeats to Willy Wise, Kostya Tszyu, and Grover Wiley.

"In fact everything in the boxing has a beginning and an end," Diaz said. "It has happened to every fighter. Julio Caesar Chávez was invincible and then he went down."