Duel at Diablo is a 1966 American Western film starring James Garner in his first Western after leaving the long-running tv series Maverick, as well as Sidney Poitier in his first ever Western. Based on Marvin H. Albert's 1957 novel Apache Rising, the film was co-written by Albert and Michael M. Grilikhes; it was directed by Ralph Nelson, who had directed Poitier in Lilies of the Field. The supporting cast includes Bibi Andersson, Bill Travers, Dennis Weaver and John Hoyt; Ralph Nelson has a cameo as an Army Major. The movie was shot on location amidst striking scenery in southern Utah; the musical score was composed by Neal Hefti.

James Scott Garner was an American actor. He played leading roles in more than 50 theatrical films, which included The Great Escape (1963) with Steve McQueen; Paddy Chayefsky's The Americanization of Emily (1964) with Julie Andrews; Cash McCall (1960) with Natalie Wood; The Wheeler Dealers (1963) with Lee Remick; Darby's Rangers (1958) with Stuart Whitman; Roald Dahl's 36 Hours (1965) with Eva Marie Saint; as a Formula 1 racing star in Grand Prix (1966); Raymond Chandler's Marlowe (1969) with Bruce Lee; Support Your Local Sheriff! (1969) with Walter Brennan; Blake Edwards's Victor/Victoria (1982) with Julie Andrews; and Murphy's Romance (1985) with Sally Field, for which he received an Academy Award nomination. He also starred in several television series, including popular roles such as Bret Maverick in the ABC 1950s Western series Maverick and as Jim Rockford in the NBC 1970s private detective show, The Rockford Files.