But the 1976 film became a phenomenon that won Oscars for best picture as well as for Avildsen as director and editing, and was nominated for seven others.
The 1984 film tells the story of a teenager hounded by bullies, who learns karate from a Japanese handyman and takes on his bully in a karate contest - and wins.
The franchise, The Karate Kid (1984), which starred Pat Morita as an Okinawan martial arts master who agrees to teach karate to a bullied teenager, brought in nearly a quarter-billion dollars at the Box Office.
"Throughout the decades, his rousing portrayals of victory, courage and emotion captured the hearts of generations of Americans", Paris Barclay, president of the Directors Guild of America, said in a statement. Nobody could have done it better than my friend John Avildsen. He later returned to the franchise in 1990 to direct Rocky V. That film also impressed Frank Capra, who was incidentally Avildsen's favourite director.
Avildsen is survived by his daughter Bridget, and his sons Ashley, Anthony, and Jonathan.
Among other Oscar nominations for "Rocky" were two for Stallone, best actor and best screenplay; plus best actress, Talia Shire; best supporting actor, Burgess Meredith and Burt Young; and best song, "Gonna Fly Now".
Stallone took to Instagram to pay tribute to Mr Avildsen, who helped usher the actor to stardom: "R. I. P".
Born in Oak Park, Illinois, Avildsen graduated from Hotchkiss School and New York University. His Save the Tiger earned Jack Lemmon an Oscar for Best Actor. In 2016, directed Derek Wayne Johnson made a documentary on Avildsen's life and career. He left quite a nice legacy of films including "The Karate Kid", "Lean on Me", the original "Neighbors" with Aykroyd and Belushi.
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