Heavyweights Junior dos Santos and Alistair Overeem will finally square off, as officials announced the bout as a co-main event for UFC on FOX 17.

Set for December 19 from the Amway Center in Orlando, the card features a headline fight between Rafael dos Anjos and Donald Cerrone for the lightweight title.

Dos Santos (17-3), a former UFC heavyweight champion, will return for the first time in over a year. He scored a victory over Stipe Miocic at UFC on FOX 13.

Overeem (39-14), an ex-Strikeforce and PRIDE titleholder, is on a two-fight win streak. He scored a March decision over Roy Nelson.

The two fighters have gone back-and-forth on social media. They were once scheduled to fight for the belt before Overeem was found to have failed a drug test.

Below is the current lineup:

UFC Lightweight Championship
Rafael dos Anjos (c) vs. Donald Cerrone

Heavyweight: Junior dos Santos vs. Alistair Overeem

Lightweight: Nate Diaz vs. Michael Johnson

Middleweight: Tamdan McCrory vs. Josh Samman

Middleweight: C.B. Dollaway vs. Nate Marquardt