UFC superstar McGregor said “I’ve decided to retire from fighting” at the weekend – it is the third time in four years he has threatened to hang up his gloves.
“Well, if you decide to come back, I will be waiting to punish you again.”
Mayweather stopped McGregor in a lucrative crossover boxing match in 2017, then retired from the ring with an exemplary 50-0 record.
McGregor has since fought twice in the UFC octagon, including a 40-second destruction of Donald Cerrone earlier this year but his future is now in doubt, although he has reversed decisions to retire twice already.
After his most recent UFC victory, McGregor received cryptic tweets from Manny Pacquiao and Mayweather.
“It’s me and Manny,” he teased about his next fight.
He then said about Mayweather: “”He’s far from retired. That rematch will happen at some stage.”
Mayweather, 43, has more recently offered to pay for the funeral of George Floyd, the African-American killed in police custody last month.
It is not the first gesture of its kind from Mayweather. In 2011 he paid the funeral costs for his former opponent, Genaro Hernandez, and for the heavyweight legend Joe Frazier.
Mayweather has suffered two recent bereavements – his ex-partner and the mother to his children Josie Harris, and his uncle and trainer Roger.
Mayweather has started training undefeated lightweight Devin Haney, which has caused friction with his former protégé Gervonta Davis who is a potential future opponent.