WBA light-heavyweight champion Beibut Shumenov wants a showdown with Nathan Cleverly.
The Welshman was installed as WBO king two weeks ago, and made a successful defence of his title at the O2 Arena.
And now he's attracted interest from Shumenov, who wants the 24-year-old to travel to the States to face him.
"The question is would Cleverly consider fighting me in United States?" the US-based Khazakstani told the BBC.
"I wouldn't offer advice to Cleverly about anything because he is his own man. However, as I mentioned earlier, the question is would Cleverly come to the US to fight.
"I would love to see a tournament with the four world champions fighting each other. Like I said, I've always wanted to unify the titles.
"I don't know if [Cleverly] is ready. You would have to ask him but my goal has always been to unify the 175lbs titles. I tried to make it happen and will continue to do so."