BIG BEAR (California) • World middleweight boxing king Gennady Golovkin accused Saul "Canelo" Alvarez of doping on Tuesday, rubbishing the Mexican fighter's claims that he had failed a recent drug test owing to contaminated meat.

In explosive comments to reporters, the Kazakh said Alvarez had benefited from preferential treatment throughout his career by the Nevada authorities, where the two men will fight in a much anticipated rematch on May 5.

Golovkin was widely believed to have won last September's first battle, when a judging controversy dominated the aftermath of the bout which ended in a draw.

Earlier this month, Alvarez was revealed to have tested positive for clenbuterol, which his promoters blamed on consumption of drug-tainted meat in his native Mexico.

Both camps are awaiting a formal ruling on the case from the Nevada State Athletic Commission but the fight is expected to go ahead.

Golovkin, often known by his nickname "GGG" or "Triple G", emphasised that he was willing to climb into the ring regardless of the outcome of the Nevada case. But he pulled no punches in branding Alvarez, 27, a dope cheat.

"Forget Mexican meat," the 35-year-old said. "Come on. I told you. This is not Mexican meat. Ask him. Ask his team, his promotion. Everything.

"Canelo's cheating. They're using these drugs and everybody's trying to pretend it's not happening. And you're asking again about meat? There's nothing about meat. Maybe it's Mexican water."

AGENCE FRANCE-PRESSE