The only way Ricky sees this bout going is in Mayweather's favour, unless it's a no-contest due to some cheap tactic by McGregor; or it's rigged and both Mayweather and McGregor are in on it together and McGregor scores a controversial win which leads to a re-match purely for purse reasons.
Mayweather is 49-0 and we are to believe he is going to be upset by a guy who's never engaged in a professional boxing match in his life? Yes Mayweather is 40 years old, where as McGregor is only 29, but when it comes to boxing age can be overlooked in favour of technique.
Mayweather may not knock McGregor out because he's more of a defensive boxer and McGregor is elusive in his own right, but he's going to score the decision regardless if it goes the distance.
Search around for the best number you can find and lay your money on Mayweather to win straight up.