'He's putting himself on a very high level. I think he's more of a four-round fighter at this point.
'He's [Mayweather] not a risk-taker anymore. He's not the most exciting guy in the world. But, he's still a great boxer. [McGregor] can't beat guys like that, in my opinion.'
The Irishman took a break from his boxing training to attend the christening of his nephew.
He proclaimed himself the "King of Ireland", as he posted a number of updates on Instagram from the famous Shelbourne Hotel.
The hotel is one of Ireland's most historic buildings, having had the nation's constitution drafted in one of it's rooms back in 1922.
McGregor and assorted family members dined in the Constitution Room and the significance of the surroundings was not lost on the UFC lightweight champion.
He accompanied a short video with the caption: "This is the room where they signed the Constitution of the Irish free state.
"It is also the venue for my nephew Harry's christening. Know and be proud of where you come from to know where you are going! #IrishRoyalty"
The "Notorious" also posted other photos, with his nephew calling him a "boss in the making" and pregnant partner Dee Devlin was also in attendance.
McGregor continues to be linked with a possible mega-fight against Mayweather and although all signs point to a contract being finalised, no deal has been announced.
A venue and date has already been inked in the diary, as T-Mobile Arena in Las Vegas has been booked for June 10.
But there are still financial hurdles to overcome, notably the involvement of the UFC who will want a slice of the action.
The contest is a potentially lucrative one, with both men targeting $US100million each, although McGregor is under contract with the UFC for four more fights and is likely to have to share his spoils.
The self-proclaimed "King of Ireland" would almost certainly become combat sports royalty, if he managed to upset the odds and prove Roach wrong in his assessment.
