Conor McGregor and Floyd Mayweather Jr. will earn perhaps nine-figure paydays while fight fans will be charged $100 to watch on TV in high def and can’t get into the arena for anything less than a $500 face-value ticket —if they’re lucky.

But in New York, where a “Hamilton” seat can cost you a rent check, there’s still a deal to be found — even in the fight game.

The fight angling to become the richest in sports history is offering fans a bargain-basement price for this weeklong smack-talking circus: Free. It’s the cleanest four-letter word uttered by the Irish UFC star McGregor and the undefeated boxer Mayweather during a foul-mouthed promotional tour that stopped Thursday at the Barclays Center.

Fans lined outside the home of the Brooklyn Nets hours before they were allowed inside the arena. They flocked in TMT gear or draped themselves Irish flags as they waited for the pair to start trading insults weeks before they exchange blows.