Teofimo Lopez Jr. called out Devin Haney after the American star stunned Vasyl Lomachenko to unify the lightweight division.
Lopez dethroned Lomachenko by unanimous decision to add the WBA, WBO and WBC 'franchise' titles to his IBF belt in Las Vegas Saturday.
The 23-year-old emerged victorious over 12 rounds at MGM Grand, where he became the youngest four-belt champion since the WBO was founded in 1988.
After snapping Lomachenko's 13-fight winning streak, Lopez (16-0) turned to 'regular' WBC champion and American rival Haney (24-0).
"Man, take me to 140," Lopez said after judges scored the fight 116-112, 119-109 and 117-113 in his favour.
"Or I could fight the two-time email world champion Devin Haney if they want that."
Haney replied via Twitter, writing: "Lopez vs Haney 2021 Let's do it! AllTheBelts".
Lomachenko had the pedigree heading into the bout, stemming back to a glittering amateur career that included two Olympic gold medals, through to winning world titles in three different divisions in the paid ranks.
But the Ukrainian star was also coming off a 14-month layoff as Lopez controlled the early rounds before withstanding a late rally.
"Just tried to keep pressuring him," Lopez said. "Just don't give him the jab, don't let him set up. Every time he did want to throw, I had something ready for him to stop the momentum.
"He was on a 14-month lay-off, and I knew it was going to take time for him to catch up."
Despite Lopez's early superiority, Lomachenko insisted: "I think the first half of the fight he got more rounds than I did, but in the second half of the fight I took over.
I definitely don't agree with the scorecards. At the moment, I thought I won. But the results are the results."