There was a time, remember, when everyone said a Conor McGregor-Floyd Mayweather boxing match was a ridiculous pipe dream.

Now that Khabib Nurmagomedov has called out Mayweather, the same kind of early response is fair to be expected. But if it sounds ludicrous, hold on for just a tick … because online sportsbook Bovada has listed a line for the fight (via ProBoxingOdds.com).

If the boxing match ever goes down, Mayweather has opened as a 20-1 favorite at -2000 against the UFC lightweight champion. The comeback on Nurmagomedov is +900, making him a 9-1 underdog.

Mayweather opened as a -3000 favorite against McGregor and closed as just a -750 favorite.

Nurmagomedov (27-0 MMA, 11-0 UFC) is coming off a dominant submission win over Conor McGregor in the UFC 229 main event to retain his title. And issues with a post-fight melee aside, Nurmagomedov wasted little time shooting for the stars by calling out Mayweather (50-0 boxing) for a money fight of his own, like the one McGregor got in August 2017.

Nurmagomedov posted a video to Instagram to initiate things.

“Hey, let’s go, Floyd. We have to fight now,” Nurmagomedov said. “50-0 vs. 27-0. Two guys never lose. Let’s go. Why not? Because in the jungle only one king. Only one king. Of course, I am the king because he cannot drop McGregor, but I drop him easily.”

Mayweather stopped McGregor with a 10th-round TKO, but never knocked him down.

Mayweather seems completely down for another crossover payday, too.

For complete coverage of UFC 229, check out the UFC Events section of the site.