UFC President Dana White is realistic, and realizes that MMA superstar Conor McGregor is not capable of winning a straight up boxing match with five division world champion Floyd Mayweather Jr.

Last week, Mayweather and McGregor kicked off a four-city promotional tour which started Tuesday at Staples Center in Los Angeles and ended Friday at Wembley Arena in London.

Four times they faced off in front of a raucous crowds. Both fighters promised a knockout, and all four times White had to step between the two fighters.

McGregor, a two division UFC champion, is stepping in a boxing ring to fight for the first time, with 10 ounce gloves at the junior middleweight limit of 154-pounds.

Mayweather, 40 years old, is coming back after a two year retirement.

"I am fighting, and he is boxing," McGregor said. "It's two men at the top of their game competing. It's two worlds colliding. That enough is reason why this is what it is."

McGregor  has been training for months to develop his boxing skills. White has received countless videos of his training sessions and admits McGregor has little to no chance in winning a "boxing" match. He says McGregor stands a good chance of pulling off an upset by roughing Mayweather up and making him feel his age, round after round.

“All I’ve seen are stuff that he’s [McGregor] sent me, videos that he’s sent me. Listen he’s not a boxer, at the end of the day, Conor McGregor is not a boxer, he’s a fighter. Conor McGregor is the bigger, stronger guy and needs to hit Floyd Mayweather and needs to hurt him," White said.

“I don’t see him out-pointing Floyd in a boxing match. I see him getting in, turning it into a fight and roughing Floyd up. I believe in this fight Floyd is going to fight traditionally the way that Floyd fights, the best defensive fighter ever.

The fight takes place on August 26th at the T-Mobile Arena in Las Vegas.