Director Sam Peckinpah insisted on changing an early expository scene in which a girl in her underwear is massaged with a vibrator. He removed the vibrator from the scene altogether and had the girl lie naked but completely covered with a fur coat. Producer Martin Ransohoff was unhappy with the shift in tone and fired Peckinpah.
In the final hand, Lancey overlaps his exposed cards similar to a solitaire row, the Queen of diamonds is the top card while everyone is discussing if he has the Jack or not. A few seconds later, the cards are reversed and the Queen is the bottom card.
In the opening card game of 5 card stud, the pot of money is shown at the dealer's left side of the table, then after a brief shot of The Cincinnati Kid's face, it is shown in the center of the table, barely in view. (at about 4:14)
When the Kid is accusing Shooter of cheating by dealing him winning hands, Shooter begins to deny it, and the Kid grabs Shooter by the lapels and bangs him into the door. When he does that, the whole door and jamb and the wall beside it visibly shake and move, showing that the wall is definitely not a real wall.