From the “in case you didn’t know” department, the original story of Rocky was inspired by Chuck Wepner, a tough ex-marine who challenged Muhammad Ali for the heavyweight title in 1975, and in a losing effort became the only opponent to knock Ali down during his championship years.

“When a young, impressionable and unknown Philadelphia resident — Sylvester Stallone — saw the Wepner/Ali fight he was instantly inspired to write the blockbuster movie screenplay, Rocky. It became one of the 20th Century’s greatest box office hits.”

[Wikipedia]

[Chuck’s Page]