UFC 239: Jones vs. Santos was a mixed martial arts event produced by the Ultimate Fighting Championship that was held on July 6, 2019 at T-Mobile Arena in Paradise, Nevada, part of the Las Vegas Metropolitan Area.

[2][3] A UFC Light Heavyweight Championship bout between current two-time champion Jon Jones and Thiago Santos served as the event headliner.

[5] The matchup was originally scheduled to take place in September 2017 at UFC 215, but dos Santos pulled out of that event, citing a failed drug test.

[8] The matchup was originally scheduled to take place in November 2018 at The Ultimate Fighter: Heavy Hitters Finale, however Melendez pulled out of the fight citing an injury.

[12] Drako Rodriguez from King of the Cage was offered to replaced O'Malley initially; however the president of the promotion, Terry Trebilcock, refused to release him.