WBA, IBF, WBO light heavyweight world champion Andre Ward believes Floyd Mayweather may close the show with a very big knockout on Saturday night, when he faces UFC superstar Conor McGregor.

The pair will collide in a boxing match at the T-Mobile Arena in Las Vegas.

McGregor, who is a two-weight champion in the UFC, is making his professional boxing debut. Mayweather, 40 years old, is coming back after a two year retirement stint.

Ward expects McGregor to come out strong in the early rounds, but quickly get winded - and that's when Mayweather will take over the entire fight.

"I think McGregor will be wild for the first three rounds, but when he starts to tire, Floyd will take over and we could see a big knockout," said Ward to Sky Sports.

The fight has created massive headlines all over the world and many feel the contest has the potential to generate the biggest pay-per-view buyrate in history. The current buyrate leader is Mayweather vs. Manny Pacquiao from May of 2015, which brought in 4.6 million buys.

Not everyone is happy with the fight, as it's viewed as a complete mismatch by most. Others are not happy with the contest being sanctioned as an official bout - which in turn would raise Mayweather's record to a perfect 50-0. And there are those who are angry with the match being approved to use 8-ounce gloves at the junior middleweight limit by the Nevada State Athletic Commission.

"Some people have spoken out against it, but I think it's good, we're talking about it and so is everybody else. Even the mainstream media want to know, so I don't think it's as bad as everybody is making out. Floyd Mayweather has put on shows for the best part of two decades, so he deserves to do whatever he wants and this isn't a sideshow, it's a massive event," Ward said.