Gennady Golovkin has outlined his desire to take on Billy Joe Saunders in a middleweight world-title-unification fight if Saul "Canelo" Alvarez is handed a doping ban.
Golovkin (37-0-1), 35, is due to face Alvarez for the second time in Las Vegas on May 5 after drawing their first highly anticipated meeting.
However, the rematch risks cancellation after the Mexican fighter tested positive for clenbuterol, but it is still scheduled to go ahead.
Alvarez's test results, which he claims came as a result of eating contaminated meat, are currently being investigated by the Nevada State Athletic Commission, and the fighter could face a ban if found guilty.
Although Alvarez's promoter, Oscar De La Hoya, remains confident the fighter will be cleared, WBA-WBC-IBF champion Golovkin has highlighted WBO beltholder Saunders as his preferred fall-back option.
"If that fight can't happen, the next step for me is Saunders, since it is my dream to get all the world championship belts," Golovkin told RingTV.
Saunders, 28, is preparing to defend his title for the fourth time when he meets Martin Murray at London's O2 Arena on April 14.
The Brit has made little secret of his desire to go head-to-head with Golovkin after calling out the Kazakhstani world champion after his dominant points victory over David Lemieux in Canada on Dec. 17.
Although Golovkin has made little effort to hide his disappointment at Alvarez's failed test, he said he is still keen for the rematch to take place.
"I was surprised this happened, because knowing Canelo and his team, I didn't expect they were using some kind of forbidden substances," he said.
"It is unpleasant to see this go in that direction. I want competition between athletes, not laboratories. A clean fight, not a medicine fight.
"I still hope the fight happens, as it is the biggest fight in boxing right now, and I would like to be on that level once again."
On the subject of the investigation, Golovkin said, "It is for the the commission to decide. There is a simple test, and it's either positive or negative. It's either you are doping or not doping."