Character mistake: Flat Top should have numerous roughing the passer calls against him in the final game. Many times he ran into Blake long after he threw the ball, but the ref never called a roughing the passer call.
Character mistake: Gail is interviewing Nick on the steps with a tape recorder. You can tell she's holding down the wrong buttons. The record button is in the up position. She's not recording anything.
Character mistake: In the very first scene, in the first shot you see a sign in Spanish that says "NO PASE por orden del departamento de arquiologia". The correct Spanish word is arqueologia.
Character mistake: We see in a flashback (so, early 1600s) the protagonist with his mother in Ruen, back in motherland France. She tells him she is praying to St. Joan (d'Arc; they are in front of a statue of hers). Joan d'Arc wasn't canonized until the 20th century. You could argue that in the eyes of the laymen she was already considered a saint. However, her son does not object and considers her a saint as well, doubling down on the statement even later on in Quebec when he does not have to humour his mother, and he is a Jesuit. He obviously should know better. (00:35:25)