Factual error: The poem Ali quotes in the movie before the Frazier fight, "Ali comes out to meet Frazier, Frazier starts to retreat, If he goes back any further, He'll end up in a ringside seat..." was in fact the poem he used before the first Liston fight and began, "Clay comes out to meet Liston, Liston starts to retreat..." and ends with the lines, "Never did they think, When they laid down their money, That they would witness, The total eclipse of the Sonny". Poor effort.
Continuity mistake: When Jefferson is forced to walk home alone, he is wearing blue jeans. When he hides in the cement things to use his inhaler, it shows him wearing khakis. Then, when he gets jumped right after by the guys on the bikes, he is wearing jeans again.
Factual error: The third member of the Yankees with a prominent role in the film is Bob Cerv (roommate of Mickey & Roger). In the film, he is with the team from Opening Day. However, Cerv was actually acquired by the Yankees in May of that year.
Continuity mistake: When the Kung Fu team is training, the coach throws an egg onto "Steel Leg's" foot. It breaks and some of the yolk gets on the ground. But when the fat player starts eating it, the whole yolk's on the shoe. (00:33:30)
Continuity mistake: When Nitro is being sent to another prison, as he is put into the back of the van the prison guard on the right has his hat knocked off, but as he closes the door his hat is back on.
Factual error: On the England shirt, you can see the badge where the three lions logo should be. But it is not there. It is the badge the England Cricket team wear on the sleeves on their shirts. [I'm assuming that the FA didn't give permission for the three lions logo to be used, but it is still a mistake].
Factual error: In the movie, the over is shown to be of six balls. In 1896 the British played cricket with a five ball over.