How much money will Nick Diaz make boxing Jeff Lacy?

More than he made in his last mixed martial arts fight.
That's according to Joey Gilbert, Jeff Lacy's manager, who gave Bloody Elbow the scoop on the cash flow distribution in the Diaz vs. Lacy fight that might be going down later this year.

"Nick Diaz will be making at least the $175,000 he made in his last MMA bout, possibly slightly more." Another interesting development in terms of the payouts followed when Gilbert said "Jeff Lacy is actually making slightly less than Diaz." He then went on to explain that Lacy was willing to take less than the 50/50 split that we discussed the last time we spoke because he wanted to make sure they got the deal done.
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"Right now we're ready to go with an independent pay-per-view, but Showtime would be crazy not to pick this up. Jeff Lacy made his name on Showtime and Nick Diaz is a champion in mixed martial arts and a Showtime fighter."
Finally, Gilbert said that the bout would be a ten round fight.

Diaz now has a rather strong amount of leverage for when he sits down with UFC President Dana White to negotiate a potential superfight against Georges St. Pierre.
The Cesar Gracie camp has made it known they will accept a booking in the UFC against St. Pierre if the terms are correct. They will also forgo a boxing match against Lacy in order to do so, again, if the contract is right.