Mayweather vs. McGregor: Cops Cracking Down On Illegal Sex Workers

Huge sporting events mean huge money for sex workers ... but cops in Vegas have a message for tourists -- if you're gonna pay for it, KEEP IT LEGAL!

With Mayweather vs. McGregor going down next weekend, law enforcement agencies will be cracking down on illegal prostitution and human trafficking in Sin City.

Of course, there are LEGAL brothels just outside the Vegas area -- but cops want to send a message that hookers, pimps and johns aren't welcome to do business within Vegas city limits (the closest legal brothel is about 60 miles from the strip).

We're told multiple law enforcement agencies are joining forces for the event -- with Las Vegas Metro PD, the Dept. of Homeland Security and other agencies working together to keep Vegas safe.