By Ernesto Castellanos, notifight.com

Former four division world champion Juan Manuel 'Dinamita' Marquez is giving Amir Khan (31-3, 19KOs) a chance to pull off the upset on May 7th, when the British boxer moves up to a catch-weight of 155-pounds to challenge Saul 'Canelo' Alvarez (46-1-1, 32KOs) for the WBC middleweight championship.

Marquez is bothered by the weight as many others are.

Khan will be at a physical disadvantage when he face Canelo, who for his last four fights has weighed in at the 155 limit. Khan is going up by eight pounds, the biggest climb of his career.

Marquez gives Khan a shot, but says Canelo's advantage in power - combined with Khan's susceptible chin - can create a knockout ending at any moment in the fight.

"It's a contest in which the Mexican fighter will get a good advantage due to the weight. However, Khan can win with his mobility and speed - but there is decent sized difference in the weight, and Canelo can knock him out at any time," Marquez said.

For his part, Marquez wants to return in May. As previously reported on BoxingScene.com, Marquez is open to the idea of a catch-weight bout with another former four division world champion, Miguel Cotto, in the fall. He says the Cotto bout would need a neutral location and ruled out New York City.

"I had a meeting with people from Cotto's team. They said they wanted the fight soon, but I told them that it was impossible for me because I need at least one fight to prepare, since I'm going on two years now without fight. I told them if they were interested I could be ready in November and they liked that," Marquez said.

Marquez said the plan is to have a ten round fight in May.

"Indeed, the possibility is that in May I could fight in the Zocalo. The idea pleases me, because the venue there could support some 95 thousand fans, which would be great," Marquez said.