UFC 194 will now feature two title fights as middleweight champion Chris Weidman faces Luke Rockhold in the new co-main event on December 12 in Las Vegas.
The featherweight title unification bout between Jose Aldo and Conor McGregor will headline the card from the MGM Grand Garden Arena.
The fight was announced via ESPN SportsCenter on Thursday night.
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Weidman and Rockhold have been on a collision course for several months just waiting for the UFC to pick a date and location for the fight and now it's official.
Weidman will look to make the fourth defense of his UFC middleweight title since winning the belt from Anderson Silva in 2013.
Most recently, Weidman dispatched Vitor Belfort in the first round of their title fight at UFC 187 by TKO.
As for Rockhold, he'll earn his first crack at UFC gold since joining the promotion as the last ever Strikeforce middleweight champion.
Rockhold has only suffered one bump in the road since joining the UFC when he fell to Belfort in his debut, but since that time he's reeled off four wins in a row including a submission victory over former champion Lyoto Machida in his last fight.
More fights are expected to be added to UFC 194: Aldo vs. McGregor in the coming days.