Freddie Roach is confident that Manny Pacquiao will retire on a high note, predicting a knockout victory for his prized fighter in his upcoming rematch with Timothy Bradley on April 9 at MGM Grand in Las Vegas, Nevada.

Pacquiao, who owns a 57-6-2 record with 38 knockout victories, has announced that his next fight will be his farewell bout, as he is aiming to focus on his political career in the Philippines.

With Pacquiao confirming his impending retirement, Roach said that he is convinced the Filipino boxing icon will end his career with a knockout victory against Bradley.

"Manny wants to go out with a bang and knock Tim out so I predict a knockout in nine," Roach told BoxingScene.

Pacquiao is favored to win against Bradley in their third fight based on their first two bouts. The former pound-for-pound king absorbed a split decision loss in June 2012 but World Boxing Organization eventually ruled that Pacquiao clearly won the bout. In April 2014, Pacquiao ran away with a convincing unanimous decision win.

Boxing fans and analysts previously questioned Pacquiao's decision to face Bradley instead of Amir Khan or Terence Crawford. Top Rank Promotions CEO Bob Arum defended their decision, insisting that Bradley is a different fighter from what he was two years ago after hiring Teddy Atlas as his new trainer.

Roach said that Bradley, who is coming off ninth-round knockout win against Brandon Rios, could improve under Atlas. But the Hall of Fame trainer is convinced that Atlas will not become a big factor in the Pacquiao-Bradley rematch.

"I got the better fighter, so I'm not worried about it," Roach said. "Manny isn't a hard guy to get up for fights. He knows he has to be at his best to win this fight. Once he's in the gym, he gives me 100 percent."

While Roach is confident that the change of trainer will not affect the outcome of the third showdown, Bradley is confident that Atlas will prepare a perfect fight plan to beat Pacquiao in April.

"Teddy and I and the team, we're going to go to the lab and we're going to devise a game plan where we're smart monster on April 9th," Bradley told BoxingScene. "It's only going to get better from here. I feel that now I have an identity of a fighter, I know what I'm about."

Bradley, who is the reigning WBO welterweight champion, holds a 31-1-1 record with 13 knockout victories.

Watch the highlights of the first two fights between Pacquiao and Bradley below.