The 42-year-old rapper and the "Prisoners" actor were welcomed by excited fans during the preview show of boxing drama, reported Aceshowbiz.
"From the minute I saw this script, I really felt like this movie had the potential to be something special. We hope that you all do, too. Jake did an incredible job... Everybody in the movie is great in my opinion," Eminem, whose real name is Marshall Bruce Mathers III, told his hometown fans.
The screening, also attended by several local boxers, was not announced as the rapper wanted to surprise his fans.
Directed by Antoine Fuqua and written by Kurt Sutter, the film also stars Forest Whitaker, and Rachel McAdams.
Eminem has collaborated on the album for the film, scheduled to release on July 24.