Khabib Nurmagomedov's manager Ali Abdelaziz claims that a fight between Khabib and Floyd Mayweather had been agreed for January 2020.
Mayweather announced on Thursday that he will come out of retirement sometime next year, although the undefeated multiple world champion told Reuters on Tuesday that he was done with boxing.
“I’ve got calls to get back into the ring, but my health is my wealth,” Mayweather said.
“Boxing is a very, very brutal sport. In the last few years a lot of fighters have died inside that squared circle.”
The 42-year-old then uploaded a picture of himself to Instagram with tape around his hands and the words "Coming out of retirement in 2020.
"@danawhite and I working together again to bring the world another spectacular event in 2020."
UFC president White then backed up Mayweather's claim by reposting the image and adding three fist emojis.
Mayweather hasn't competed since his 2017 victory over Conor McGregor that took him to 50-0 in boxing, but he now seems set for a UFC debut in the New Year.
There have been suggestions that could mean a rematch with McGregor, although this time in the octagon, but so far no opponent has been confirmed.
However Abdelaziz appeared to confirm on Saturday that Khabib won't be that opponent.
The Russian's manager posted a promotional video advertising a Mayweather vs Khabib bout which would take place in Saudi Arabia in January 2020.
Alongside it he wrote: "This was originally planned but the big Dady of combat sport today @danawhite make @floydmayweather hide for a lil bit.
"3 of us knew what happened but to be honest I’m glad to see @danawhite with @floydmayweather finally got a good promoter to promote his fights."
Khabib will fight Tony Ferguson in April or May.
