Former world champion Sugar Ray Leonard has labelled the proposed bout between Floyd Mayweather and UFC star Conor McGregor the biggest mismatch in boxing history.
However, fuelled by hype and social media, it's become a contest sporting fans want to see.
"It will be successful, financially," Leonard told the Telegraph.
"It is intriguing. It reminds me of when Muhammad Ali fought Inoki. I saw it just the other day. Back then I loved it but...if they decide upon boxing with McGregor, Mayweather wins hands down. But if McGregor was able to kick..."
After retiring with a 49-0 record almost two years ago, 40-year-old Mayweather has said this was the only bout which interested him, but it will only go ahead as a boxing match.
"It's two different sports trying to be one sport. Would it sell? Yes it will sell. There's a curiosity which is a factor. But it won't be what people are anticipating," Leonard said.
"It is not a fight which will please the boxing purists.
"The fact that we boxers deliver punches is so different to what they do. There's more looping and what have you because they also have to be in position to be able to kick and be on balance to deliver that elbow or whatever shot they have.
"It will be interesting. I'm struggling with words. I'm trying to think how best to describe what could and what would happen. Being just boxing, it's Mayweather by a long shot."