LOS ANGELES — Steve McQueen’s historic saga “12 Years a Slave” topped the nominations list for the 20th annual Screen Actors Guild Awards Wednesday, cementing it as a solid Academy Awards prospect with four nominations.

John Wells’ dysfunctional family adaptation “August: Osage County,” which hits theaters Dec. 25 and features an all-star cast including Meryl Streep and Julia Roberts, also picked up awards-season momentum with three nominations, including outstanding performance for the cast.

The SAG nominations are one of Hollywood’s first major announcements on the long road to the Oscars. Also key are the Golden Globe nominations, which will be revealed this morning.