Keith Thurman will have to go against a wall if he aims to beat Manny Pacquiao in their upcoming fight on Saturday at the MGM Grand Garden. Justin Fortune, Manny's long-time strength and conditioning coach, thinks that the American boxer is not smart enough to keep the Filipino boxer at bay.

Fortune believes that Thurman would try to do anything to win. But he's "just not smart enough and fast enough" against the Filipino boxing legend.

Speaking with the media, Fortune said that Manny has an advantage in "Speed, strength, and experience." At 30 years old, Thurman would have to pull his wits against a more polished and experienced boxer like Pacquiao.

Floyd Mayweather and Manny Pacquiao
Floyd Mayweather and Manny Pacquiao could have a rematch next year. In this picture, Pacquiao throws a right at Mayweather during their welterweight unification championship bout at MGM Grand Garden Arena in Las Vegas, Nevada, May 2, 2015. Al Bello/Getty Images

The former eight-division boxing world champion is still competing at the highest level despite turning 40 last December. Fortune might have had something to do with it, and the Australian trainer is confident that they will triumph against the younger Keith Thurman.

Fortune added that their camp isn't "really afraid of anything," but he cautions that Manny must be careful not to walk into Thurman's trap. The current super welterweight champ is undefeated in his 29 fights, and 22 of those came from knockouts.

Manny's camp said that their goal is to put pressure on the defending champ. Fortune believes that Thurman won't be able to withstand Pacquiao in the later rounds.

The Filipino pugilist from General Santos City, Philippines throws a lot of punches in his fights, and his camp believes that it will overwhelm Thurman. Fortune added that he doesn't see the American boxer to "maintain that pace."

His trainer expects Manny to weigh 146 to 147 pounds in the official weigh-in and he thinks he's in better shape than his previous fight against Adrien Broner. On fight night, Fortune wants the former eight-division world champion to gain 6 pounds. He estimates that Thurman will try to bulk up at least 160 pounds on fight night.

His camp isn't worried about the weight difference as it poses little concern for Fortune. He thinks that a knockout will happen if Pacquiao wants it, but he'd rather have the Filipino boxer to pick his shots.

In his last two fights, Manny was able to knockout Argentine Lucas Matthysse, and outpoint Adrien Broner in a dominating win. Fight analysts believe that the fighting senator would be the aggressor, but Thurman's reach could eliminate his advances.