Saul 'Canelo' Alvarez says Gennady Golovkin is not yet worthy of facing him in a middleweight world title showdown.
WBC champion Alvarez will put his belt on the line against British underdog Amir Khan in Las Vegas this weekend, the Mexican's first defence of the strap he won against Miguel Cotto in November last year.
Undefeated Golovkin is the IBF and WBA super middleweight champion and is on a fearsome run of 22 knockout victories, while his 16 title defences are bettered only by Bernard Hopkins in the division's history.
Alvarez and Golovkin are on a collision course, with the latter pegged as the Mexican's next mandatory fighter.
But Alvarez is not impressed by the standard of Golovkin's recent opposition and doubts his ability to step up.
"Fighting the type of opponents he fought a couple weeks ago, come on, that's not going to bring this fight," Alvarez said.
"He needs to work his way up, he needs to earn his shot.
"He would have to fight somebody who has skill, somebody that brings it. Yes, he has all these knockouts, but who has he fought?"