Factual error: In one game the camera pans to Herb and behind him we can see a man wearing an Under Armor hat. Under Armor didn't come out until 1996.
Factual error: There indeed was a moment in the game (vs. USSR) where Jim Craig was shaken up, but contrary to what's shown in the movie, the hit did not happen as the Soviets scored a goal. Furthermore, if a goalie is that flagrantly knocked down and out so that a teammate can get a shot off, it should be a two-minute penalty for "goaltender interference" and the goal disallowed.
Factual error: In several scenes showing Ken Morrow #3, he is shown as being a left handed shooter.He was actually a right handed shooter.
Factual error: When Coach Herb Brooks is seen walking through the Olympic Village, Italian athletes are seen walking by with their green Olympic team jackets on. It says "Italy" on the backs of their jacket, but countries use their OWN language when putting their names on their jackets. Italy always goes by "Italia" on their uniforms.
Factual error: The movie shows that in the third period there was a Slashing penalty to 16 (Petrov) at 2:47, which gave rise to the game-tying power-play goal by Johnson. The Slashing penalty was actually to 9 (Krutov) at 6:47, four minutes later.
Factual error: In the movie, after Mark Johnson scores the last-second goal in the first period against the Soviet Union, the ref indicates that the goal counts and time has expired. Both teams therefore go back to the dressing rooms. In the actual game, the ref ordered the timekeeper to put one second back on the clock, and called the players (most of whom had already gone back to the dressing rooms) back out to the ice for a face-off, to make the end of the period official.
Factual error: After the tie with Norway, Coach Brooks orders his entire team skate drills over and over again. Two of the players shown skating the drill, Buzz Schneider and Jim Craig, weren't on the ice on this occasion. Craig didn't play in the game, although Schneider did - he was ejected earlier and already dressed in street clothes when all that went down.
Factual error: The film was excellent throughout in duplicating the hockey equipment that the players used during the late 1970s and early 1980s - with one notable exception - the players are wearing CCM helmets from the late 1990's instead of the models worn in 1979/80.
Factual error: Rob McClanahan never actually cheap-shotted Jack O'Callahan to cost his team the 1976 NCAA championship, as described in the movie. McClanahan was a senior in high school at the time. Furthermore, although O'Callahan did have some hatred toward McClanahan, they never had a fight at any of the practices of the 1980 Olympic team.
Continuity mistake: There is a scene during the training camp in which we see a manager of the team crossing off players names with a blue pen. We can see him crossing the same name off twice in different shots.
Factual error: In every single hockey scene the rinks are small, NHL-size rinks. In reality, Olympic hockey was always played on the bigger "European-sized" rinks. (TV footage from the 1980 tournament confirms this) Even the game in Norway is played on a small rink.
Factual error: After Baker scores the last-minute tying goal against Sweden, we see the opening of one of the ABC television broadcasts of the Olympics as it appeared in 1980. The specific arrangement of the Olympic Fanfare music we hear, however, did not exist until a few years later. It's an arrangement by John Williams that was made for the 1984 Olympics. The crash cymbals and chimes that accompany the opening tympani notes give it away.
Deliberate mistake: It wasn't Mike Eruzione shouting his own name that finally convinced coach Brooks to stop making the players do sprints. It was Mark Johnson, who smashed his stick against the glass in a fit of rage.