Espinoza said the fight came together quickly after McGregor and the UFC reached agreement last month on their end of the deal and Mayweather's team pushed for the fight in recent days.
Mayweather is a -1,100 favorite at the Westgate SuperBook in Las Vegas, with McGregor paying back +700.
The boxing format heavily favours the undefeated Mayweather (49-0, 26 KOs) who many consider to be the best pound-for-pound fighter in the world. But the reason Conor McGregor's as big as he is is he'll fight anybody, anywhere, anytime.
The fight, which will be McGregor's first professional fight inside a boxing ring, is widely expected to be the highest grossing bout of all time, with the Irishman set for the biggest payday of his career by far, with $100 million set to come his way. Mayweather and McGregor eventually went back and forth with each other in the media and on social media talking about a possible fight, but making a deal was another story.
U.S. 'strongly condemns' attack near London mosque
But Mr Trump himself has not commented directly, instead taking to Twitter to attack Democrats and endorse Republican candidates. According to multiple reports and social media posts, the van ran over people leaving the Finsbury Park Mosque .
Cristiano Ronaldo won't quit Real Madrid - club boss
But will he leave Real Madrid? "I have not talked with Cristiano. but they tell me has been treated badly in this country". His agent, Jorge Mendes (who also represents Mourinho), claimed in 2015 that his release clause is over $1 billion.
Indian-American Among 12 New Astronauts Chosen By NASA
Both will train two years as Astronaut Candidates , then assigned technical duties before receiving their flight assignments. Three candidates hold degrees from the Massachusetts Institute of Technology, and three graduated from military academies.
DUP talks not going as expected - Sky sources
Recent political agreements in Northern Ireland have essentially been negotiated between the DUP and Sinn Fein. To focus minds, the government has given parties a discussion paper setting out key areas for agreement.