Trainer Abel Sanchez believes the highly anticipated showdown between middleweight superstars Saul "Canelo" Alvarez and Gennady "Triple G" Golovkin might not push through this year.

Sanchez said that the Canelo-Golovkin fight is the biggest possible bout in boxing today but he doubts if it will happen this year despite the fact that World Boxing Council has already ordered both fighters to collide in the second half of the year.

"I think that fight is already one of the biggest fights in boxing," Sanchez told ESPN Deportes, via BoxingScene. "For me it's the fight everyone wants to see, but I think that neither Canelo nor Oscar De La Hoya is going to do it this year despite what they WBC says."

WBC has already announced that Canelo, the reigning WBC middleweight champion, will lose his title if he decides not to face Golovkin, who is the mandatory challenger for the crown. In the event Canelo choose to face a different opponent later this year, Golovkin will eventually be named as full WBC middleweight champion.

One of the biggest hurdles for the bout is the weight issue, as both camps have insisted that the showdown should happen on their own terms. Canelo demands a catchweight of 155 pounds, while Golovkin wants the fight to happen at 160.

Alvarez, who won the WBC middleweight title via a unanimous decision win against Miguel Cotto in November, will face Amir Khan on May 7 at T-Mobile Arena in Las Vegas. Like his previous bout, Canelo asked for a 155-pound catchweight.

But for his mandatory defense against Golovkin, Sanchez insisted that Alvarez should agree to stage the fight at 160 pounds, reiterating that Canelo does not have the leverage because he will be stripped off his title if he does not agree to defend it against the Kazakh champion.

"The World Boxing Council has its rules which have been around for many years, and the weight for that division is 160-pounds," Sanchez said, via BoxingScene. "Other Mexican fighters who fought for that championship, they didn't do it at a catch-weight. It's a mandatory world championship fight, and it has to be at 160 pounds or less."

Sanchez added that Canelo could weigh 155 pounds on fight night but should not force Golovkin to trim down to the same weight, calling the demand "unacceptable" because it will favor Alvarez, who is naturally smaller than Triple G.

Golovkin, who holds a 34-0 record with 31 knockout victories, is the reigning International Boxing Federation, International Boxing Organization and World Boxing Association middleweight champion.