The rich get richer.

UFC 194 has added another huge fight as two of the world's best grapplers will face off when Demian Maia takes on Gunnar Nelson on Dec. 12 in Las Vegas.

UFC officials confirmed the fight on Friday.

Maia has been on a tear lately, winning his last three fights, including a victory over previously undefeated prospect Ryan LaFlare and a dominant one-sided performance to down Neil Magny in his last bout.

The win over Magny stopped his seven-fight win streak as Maia took another step forward in a very deep and tough welterweight top 10.

As for Nelson, he bounced back from the first loss of his career back in July when he took out Brandon Thatch by rear-naked choke in the opening round.

Nelson is a teammate and training partner of UFC 194 headliner Conor McGregor, so it's likely the Icelandic fighter will join the interim featherweight champion for his upcoming camp as they both prepare to compete on Dec. 12.

Both Maia and Nelson are high-level Brazilian jiu-jitsu practitioners, so if this fight hits the ground it could turn into a grappling exchange for the ages.

Maia vs. Nelson joins a stacked lineup for one of the biggest cards of the year with a slew of top-10 fighters already matched up on the show, not to mention McGregor's title bout with Jose Aldo and the middleweight title fight between Chris Weidman and Luke Rockhold set as the co-main event.