Stout is dealing with the unexpected passing of his longtime trainer and brother-in-law Shawn Tompkins earlier this month. UFC officials confirmed the switch to ESPN.com Monday.
It will be the fourth trip to the Octagon this calendar year for Cerrone (16-3), matching the most in his career. Cerrone is currently riding a five-fight win streak, including an impressive first-round TKO over Charles Oliveira on Aug. 14.
The Greg Jackson product is 0-3 in title fights, but a perfect 16-0 otherwise.
Siver (19-7) also looks to strengthen his case for a run at the title. The German lightweight has won four straight and eight of his last nine.
He turned in a terrific performance at UFC 127 in February, scoring an upset win over George Sotiropoulos in Australia. In his last fight, Siver won a somewhat controversial decision over Matt Wiman at UFC 132.
Brett Okamoto covers mixed martial arts for ESPN.com.