The fight is nearly finalized, but the stakes have not yet been defined. Current light heavyweight champion Jon Jones announced on social media Monday that he is vacating the 205-pound title, saying that it is "officially up for grabs."
Jones (26-1) last defended his title against Reyes (12-1) at UFC 247 in February. Jones won via unanimous decision, although there was some controversy, as some experts scored the fight for Reyes. Reyes has since stated in multiple interviews the UFC has discussed an immediate rematch with Jones with him, but Jones has made it clear he's not interested in the fight.
Following Saturday's heavyweight title fight between Stipe Miocic and Daniel Cormier, Jones actually teased a move to the heavyweight division. He wrote on Twitter that he would be seeing the heavyweight world championship "very soon."
Reyes, of California, has only lost to Jones in his professional career. Blachowicz (26-8) has been on a tear as of late, winning seven of his last eight contests, including stoppages over Corey Anderson, Ronaldo "Jacare" Souza and Luke Rockhold.