Born Joseph Minieri in Brooklyn, Santos was a football player at Fordham University and turned semi-pro before finding a new avenue in acting.
He worked blue-collar jobs until his friend Al Pacino helped him get a role in the 1971 movie Panic in Needle Park.
From 1974-1980 Santos played Becker, the friend of the easygoing ex-convict-turned-private investigator Jim Rockford (played by James Garner) in The Rockford Files. He was nominated for a Primetime Emmy in 1979.
Santos' numerous other TV credits included Magnum, P.I., Hardcastle and McCormick, a.k.a. Pablo and Hill Street Blues.
In 1990 he appeared on NBC daytime soap opera Santa Barbara as Cy Agnew, a friend of Phyllis Blake (played by Stella Stevens).
He later had a recurring role as Angelo Garepe in The Sopranos until his character was killed and tossed into the trunk of a car.
Santos is survived by his wife, Mary, and two children.