Revealing mistake: At the end of the movie, when Ace is at the stadium and he attacks the mascot, his name is called and he looks up to smile and wave. He is surrounded by players from the Miami dolphins, but if you look through the crowd of players you can see the stadium seats are empty.
Revealing mistake: When Ace's car flips over you can see the left wheel is elevated over the bush. If you look closely there is a wooden plank there to help the car lift itself over the bush. The other mistake in the shot is that there is no conceivable way the bush would have flipped the car. Unless there was something very solid in front of the bush, the car would have just gone right through the bush.
Revealing mistake: After Ace loses the guys in the car chase who kidnap Dan Marino, Ace goes hurtling through the park in his car and smashes through a picnic table. Just before his car flips you can see his windshield is smashed but no holes through it. As the car flips over the bush there is a sizeable hole in the windshield on the drivers side. Its likely the hole was for the stunt driver to look through on the flip. Ace in his car has to keep his head out the window to see anything in front of him (because of the smashed windshield). On the flip the guy has his head in the car. Later on the hole has fixed itself. We see this as Ace is driving Dan Marino to the Superbowl the windshield is still smashed but no hole and throughout the film its made very clear Ace doesn't have the money to fix it up at any point.
Revealing mistake: In the scene where Ace visits Woodstock's secret office at the music club, pay attention to the computer screen when Ace asks him to tap into the aquatic supply stores to track the sale of equipment for transporting a dolphin. Woodstock says, "All right, we got marine winch, sling, feeder fish, 20,000 gallon tank..." As he is saying this, the computer screen shows a bunch of non-related items (plates, cups, concrete, stone) with crazy numbers that don't make sense. It was as if someone was in a hurry to create a fake spreadsheet to use in the movie that they just pounded on the keyboard and a bunch of numbers came out. If you look through all of the items, it's actually funny how they are so varied (dog food, speakers, sneakers, soup, chairs) and have nothing to do with the story. Many of the items also repeat with different sets of numbers.