Factual error: At the beginning of the film, in the shots of the players in action being voiced over by Comiskey, Cicotte is marking the ball with his fingernail. You can see the modern logo of the sporting goods company "Rawlings" on the ball. It can be seen even more later in the film when Comiskey's assistant is turning a team-autographed ball over in his hands. Rawlings did not start making official major league baseballs until 1976, and even if they had made them in 1919, they very likely did not have the exact same logo. (00:04:30 - 01:28:55)
Trivia: The film is based on the real-life events of the 1919 Black Sox scandal, in which members of the Chicago White Sox were charged with "throwing" the World Series (i.e. losing on purpose). Even though many people believe he wasn't involved, "Shoeless" Joe Jackson was banned from baseball and hasn't been inducted into the Baseball Hall of Fame because of that.
Chick Gandil: You go back to Boston and turn seventy grand at the drop of a hat? I find that hard to believe.
Sport Sullivan: You say you can find seven men on the best club that ever took the field willin' to throw the World Series? I find that hard to believe.
Chick Gandil: You never played for Charlie Comiskey.
Hired Killer: You're gonna lose tomorrow.
Lefty Williams: Oh, is that so?
Hired Killer: I know it for a fact. That your wife?
Lefty Williams: Yeah, what's it to you?
Hired Killer: You don't lose tomorrow, she dies.
Lefty Williams: Who sent you?
Hired Killer: You made a promise to certain people.
Lefty Williams: You son of a bitch.
Hired Killer: You can't protect her. If I don't do it, somebody else will. First inning, Mister Williams.