The war of words between Conor McGregor and Floyd Mayweather Jr continued with the boxer's father Mayweather Sr now taunting the Ultimate Fighting Championship (UFC) lightweight champion.

The fight between the UFC star and the boxing legend has been in the works for over four months now and with UFC president Dana White softening his stance, it is a matter of when rather than if the bout will take place.

Mayweather Jr confirmed he will come out of retirement to fight McGregor and the latter is confident that he will deliver the American boxing legend's first career loss when they step into the ring. The two camps have been in talks about the fight and the Irishman's manager Audie Attar has confirmed they were going in the right direction.

Mayweather Jr's father, who is a former welterweight boxer, has dismissed McGregor's chances against the five-division boxing world champion. The 64-year-old believes 'The Notorious' is just about the talk and claimed that he could kick Mcgregor's ass if they were ever in the ring together.

"He don't want that fight. Floyd's gonna turn him upside down," Mayweather Sr told, as quoted by MMA Fighting.

"That be like you and Floyd in the ring! [Laughs]. He looks bad in the ring. That's a done deal right there. They've already showed the best that he's got," he added speaking about McGregor's boxing training videos.

Floyd Mayweather Sr
Floyd Mayweather Sr writes off McGregor's chances of beating his son Mayweather Jr Reuters

"He ain't nothing but talk! I told them people on the TV already, forget about Floyd. Let's throw Floyd to the side. Here I am, I'm a 64-year-old man and I'll beat your ass. I'll beat the s**t out of McGregor! Anytime he wants it, let's go," Floyd Mayweather Jr's father added.