Continuity mistake: During the final pool sequences, there's a quick glimpse of the main character's left (broken) wrist. It's normally all purple and gross looking, but in a brief shot, you can see his left hand shooting the pool cue and there is no purple swelling.
Revealing mistake: When Uncle Mike and Johnny go upstairs at the party to hustle Phil and company, Phil shoots the eight ball towards the corner pocket, and the sound effect indicates he made the shot. Phil says, "That's how we do it," but right as he says this, the eight ball is seen slowly rolling back into the shot, revealing he actually missed the shot.
Continuity mistake: Uncle Mike can be seen in the background in a shot of the final game before he is shown arriving at the poolhall.
Continuity mistake: At the end of the movie when the main character takes his stack of money and wraps it in his light jacket. As he walks with it in hand he leaves the building while talking to his opponent. Upon exiting the building in the next shot, he's wearing the jacket and there is no sign of where the large stack of money went.
Factual error: When Brad does the jump shot to make the 8-ball, we can see the cue ball as it leaves the rail, and there is no way that it could result in the position on the nine ball, in the next frame.
Audio problem: When Danny is singing at the club, it is obvious that he is lip syncing as his mouth is just slightly ahead or behind the words. When the song finishes there is about 1 to 2 seconds of vocals after Danny has stopped singing altogether.
Continuity mistake: When Johnny is congratulated for his victory by Danny and his friends outside, there's a scene where they push him around and it alternates between a normal shot and a closeup to Johnny's face. It's very easy to spot that the closeup is definitely another separate shot because the expression on his face changes from one to another pretty obvious.
Continuity mistake: In the beginning of the film when Jon Doyle is in the pool hall with the "brothas" and he starts saying that "quiet as a church" quote, the people playing pool in the background disappear as do the balls on the tables between some shots.