Freddie Roach is convinced that Amir Khan has a better chance of defeating Floyd Mayweather than Marcos Maidana, who will look to avenge his defeat to the former pound-for-pound king in their rematch on September 13 in Las Vegas.

Roach said that Maidana has no chance against Mayweather because the unbeaten champion is already familiar with his style, insisting that Khan, next to Manny Pacquiao, has the best tools to put Floyd Jr. into a lot of trouble.

In an interview with BoxingScene, Roach said that Khan's speed and athleticism are perfect tools to become a strong threat to Mayweather, who could consider facing the Briton if he wins again in his rematch with Maidana.

"Khan has good speed, he is a good athlete. He just stays in the pocket for too long sometimes. He wants to exchange too much. He could possibly be a threat because he's very athletic. He's very fast. I see Amir doing well with Mayweather," Roach said.

The Hall of Fame trainer, who handled Khan before the former light welterweight champion decided to part ways with him and hire Virgil Hunter, said that the Bolton, England native has shown different tactics over his last three fights.

Roach said that Khan has been holding his opponent a lot to avoid counter punches. While the 27-year-old managed to use it to his advantage in his last three bouts, the 54-year-old trainer insisted that such tactics won't work against a fighter of Mayweather's caliber.

"You know the thing is, his new trainer taught him how to hold. That's the biggest thing changed that I see - is that he'll throw a combination and hold now," Roach said. "That's a little bit boring for the fans and if you try to hold Mayweather - you're not going to have success holding him, because once you reach for him he's going to tag you. He's way too sharp a fighter for that."

Khan, who is looking to return to the ring in December, will likely face Kell Brook in his next fight where a win could finally lead to his dream showdown against Mayweather in 2015.