Rolando Castellanos, 30, pleaded no contest to the murder charge at a brief hearing in Alameda County Superior Court on Tuesday and is scheduled to return to court Dec. 10 for a pretrial hearing.
Ramirez was found shot to death in the 9700 block of C Street near Elmhurst Park at about 12:10 a.m. on Feb. 19. He lived several blocks away.
Castellanos was charged in the case on Aug. 16.
Oakland police Officer Bradley Baker said in a probable cause statement filed in court that Castellanos was identified as a person who chased down and shot Ramirez after Ramirez stole a vehicle that belonged to Castellanos' brother, Mario Castellanos.
Baker said Ramirez was shot multiple times with two different guns.
Oakland police were not available for comment on the case Wednesday morning.