Factual error: In more than one scene you can hear the sounds of a steam locomotive chugging and blowing the whistle. Steam locos were almost entirely phased out by the early 60's, and none ran in Philadelphia at the time this movie was made.
Continuity mistake: Tony, Apollo's trainer, gets into the ring twice at the end of the last match.
Revealing mistake: During the fight, it appears that the filming is done in FF to make it more dramatic. If you look at the movement of the crowd, it seems to be sped up. Still, masterfully done on a low budget.
Audio problem: When Rocky is in the locker room with Spider after the first fight, Spider supposedly says (according to subtitles and closed captioning), "Hey. You really got lucky," but that's an obvious post-production overdub. His lips are saying "sometimes".
Continuity mistake: In Rocky's first match at the church, when he gets to his corner a towel on the ropes disappears.
Continuity mistake: Around the beginning while Rocky stops by at Adrian's store, she has 3 boxes which become blue cylinders.
Continuity mistake: While Rocky is getting money from a guy, he drives a green cart and is wearing a helmet that disappears between shots.
Continuity mistake: Rocky and Paulie are going to Adrian's place, Paulie has a bottle in his right pocket but then inside the house it's on his left side.
Continuity mistake: The number 2 on Rocky's door disappears during the film.
Continuity mistake: After Rocky gets to Paulie's job he punches a piece of meat and gets some blood on his hands but it disappears a few shots later.
Continuity mistake: Before the two girls ask for an autograph from Rocky, there is an extra with a hat and glasses in the gym that changes his position between shots.
Other mistake: After Paulie gets mad in his place using the bat, he breaks the lamp and the room goes dark, but there's a second lamp which should be illuminating the room.
Revealing mistake: While Rocky is running through the small market, on the street people are looking at the camera.
Continuity mistake: When Rocky is inside the pet store for the first time he picks up a can of turtle food and then reaches into his pocket. The next shot is side on and he is holding the can with both hands and Adrian, who was facing side on to the cash register, is now facing it.
Answer: It's pretty inaccurate. Real life fighters would tire out long before the 15th round after throwing so many haymakers (knock out punches). The amount of punches that connect clean without a knock out is also unrealistic. Creed doesn't seem to ever miss with his punches. Even an inexperienced boxer should be able to see at least a few punches coming and move to avoid them, Rocky seems to have no defense at all. The reaction to being punched is exaggerated for dramatic effect (Creed being lifted off the ground due to the power of Rocky's body punches, Rocky's head being thrown back due to the power of Creed's jab). It is also likely, though this is debatable, that the fight would have been stopped prior to the 15th round as both fighters could hardly stand going into that round.
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