In March 1975, Sylvester Stallone watched Chuck Wepner, a journeyman boxer nobody expected to last three rounds, go fifteen rounds with Muhammad Ali. Wepner knocked Ali down in the ninth and survived until the final seconds before a technical knockout ended the fight. Three and a half days later, Stallone had written the screenplay for Rocky.
Producers Irwin Winkler and Robert Chartoff loved the script and offered Stallone $350,000 for the rights, with the condition that a bankable star like James Caan or Robert Redford play the lead. Stallone, then so broke he had sold his dog to pay rent, refused every offer unless he could star in the film himself. Eventually, the producers agreed, slashing the budget to $1 million and shooting the film in 28 days across Philadelphia in early 1976.
