Robert Shaw injured his knee and incorporated the resulting limp into his performance. According to "You'll Never Eat Lunch in This Town Again" by Julia Phillips, Shaw split all the ligaments in his knee after slipping on a wet handball court at the Beverly Hills Hotel a week before filming started. He had to wear a leg brace during production which was kept hidden under the wide 1930s style trousers he wore.
In the bathroom scene Hooker can be seen saying "He didn't tell me you was a fuck-up either". This has been looped to replace it with the less profane "He didn't tell me you was a screw-up either". (The grammar error is scripted).
A magical plot, dead on art direction, brilliant supporting roles (most notably Robert Shaw, ya falla?), and the guiding hand of Redford/Newman chemistry make this one of the Hollywood's great films. "The Sting" is a hallmark of the "Golden Age" of American film, and has molded not only countless films, but numerous genres, few of which have met the challenge of its master.