The Mayweather vs. McGregor megafight is finally here.

Undefeated welterweight boxer Floyd Mayweather Jr. will come out of retirement to face UFC superstar Conor McGregor on Saturday, Aug. 26, at T-Mobile Arena in Las Vegas. Mayweather vs. McGregor tickets are expected to cost anywhere from $500 to $10,000.

MORE: Mayweather vs. McGregor results

Mayweather, regarded as one of the best pound-for-pound boxers of all time, opened as a huge favorite to beat McGregor in the boxing match, but the underdog's odds were slashed in half after their world tour.

Mayweather last fought on Sept. 12, 2015, with a win over Andre Berto to push his record to 49-0 and retain his welterweight championship. McGregor is 21-3 as an MMA fighter and has won UFC championships at 145 and 155 pounds. Mayweather and McGregor will fight at 154 pounds, according to UFC President Dana White.

MORE: Mayweather vs. McGregor odds

How do the two match up? Here is everything you need to know about the Mayweather vs. McGregor megafight.

What date, time is the Mayweather vs. McGregor fight?

Mayweather vs. McGregor will take place at T-Mobile Arena in Las Vegas on Saturday, Aug. 26. The main card starts at 9 p.m. ET, but Mayweather and McGregor aren't expected to enter the ring until around 11:30 or even midnight. UPDATE: The fight has been delayed due to PPV issues.

How to watch Mayweather-McGregor fight live on PPV

Start time: 6 p.m. ET (prelims), 9 p.m. ET (main card)

Location: T-Mobile Arena in Las Vegas

TV: Order Mayweather vs. McGregor on Showtime PPV

Live stream: Showtime PPV online | Showtime PPV app

Prelims: Fox Sports Go

Mayweather vs. McGregor PPV price, ordering info

Mayweather vs. McGregor will be available in the U.S. on Showtime boxing pay-per-view with live streaming available for various devices. The PPV fight will cost $99.95 in HD (or $89.95 for SD). The fight is also available to stream on UFC.TV, but we wouldn't recommend that after the app crashed before Mayweather vs. McGregor even began.

In Germany and Austria, live streaming of the fight will be available on the DAZN platform, in some cases for free. You can find out more about coverage in this region from SPOX.

Mayweather vs. McGregor odds

The opening moneyline tabbed Mayweather as a huge favorite at -2,250 with McGregor at +950. It quickly dipped to -1,100 for Mayweather and +700 and the early wagers had the line down to -800 for Mayweather and +500 for McGregor. What does that mean? For the laymen, it means that a $100 bet on McGregor would win $500 plus the original wager back if he were to win. But in order to win $100 with a Mayweather victory, someone would have to place a wager of $800.

As of mid-July, McGregor was being given 7/2 odds (+350) after his world media tour, while Mayweather dropped to a 1/5 (-500) favorite. Check here for updated Mayweather vs. McGregor fight odds.

Mayweather vs. McGregor purse

UFC president Dana White previously stated Mayweather could pocket around $100 million for the fight, with McGregor hauling in around $75 million, which would be a record payday for him. However, Mayweather thinks he could bring in as much as $350 million. The pay-per-view is expected to gross around $475 million.

Tale of the tape, records

Matchup Mayweather McGregor Records 49-0, 26 KOs 21-3, 18 KOs Ht/Wt 5-8, 147 5-9, 154 Reach 73 inches 74 inches Age 40 28

Details for Mayweather vs. McGregor fight

The fight will be a 12-round bout at 154 pounds and the boxers will each wear 8-ounce gloves. The undercard for the main event is expected to include only boxers under Mayweather's promotion firm, Mayweather Promotions. Those boxers include Badou Jack with WBA world light-heavyweight champion Nathan Cleverly as a possible opponent. IBF super featherweight champion Gervonta Davis could also defend his belt.