Continuity mistake: In the last inning of the championship game, Buttermaker opens a beer in a short brown bottle (perhaps a Pabst Blue Ribbon, Red White and Blue, or Red Stripe) right before Amanda grounds out. When he exits the dugout following the at-bat, he's holding a Coors.
Continuity mistake: In Kelly Leak's first shown at-bat, he hit a home run to win the game, and the team the Bears defeated was sponsored by Denny's, as you can see from their catcher's logo when Kelly crosses the plate. Problem is, Denny's sponsors the Yankees, who went the entire season undefeated. We know this because in several scenes, including the one after the home-run where the head lady mocked the Bears' victory, you saw the standings where the Yankees had no losses.
Continuity mistake: In the Bears' second to last game against the Athletics, an announcement is made early in the game that the Bears are winning 1-0. But later in the game when you see the scoreboard, it shows the Athletics scored the first run of the game in the top of the second inning.
Continuity mistake: In the last inning of the final game, you saw the Yankee catcher making fun of Ogilve, and it was clear he had blond hair. But in the final at-bat where Kelly tried for a grand-slam but was tagged out by the same catcher, he had brown hair.
Continuity mistake: When Buttermaker puts Amanda's arm in the icy water, he is seen taking out a beer. When the camera changes there are no beers on the bench and he then starts taking them out. Also as he removes beers, the water level goes down in the bucket. After they are removed, the water level is up near the top.
Continuity mistake: It appears that the first kid over to Joey Turner to get the ball during Engelberg's infield home run is Billy the replacement pitcher, moments later we see that he is on the bench and not in the game.
Continuity mistake: The shadows change dramatically throughout the games (especially the championship game). Shot all different times of day at random.
Audio problem: After Turner tells his son Joey to throw to Engleberg low and outside, Joey replies "But Dad - I wanted to strike him out", however his mouth doesn't move at all and the volume on this line is much louder, so obviously dubbed in.
Character mistake: After Loopis makes that bumbling bad play in right field that costs the Bears a game, in the dugout Tanner harasses Loopis and says "we would have won if it weren't for you." This statement is incorrect because the score was tied 0-0 in the last inning when Loopis made that bad play to make them lose 1-0... so although the Bears may have had a chance to win if extra innings were played and this play DID make them lose, a "win" wasn't guaranteed the way Tanner came out saying it.
Continuity mistake: In the championship game, when Buttermaker pulls Amanda off the mound and calls in Stein, He sends Amanda to left field. However, the very next hit is hit to Lupus, and you see Kelly Leak run over from left field to field the ball. Also, when Lupus makes the catch a bit later, you see Ahmad run over from left field to congratulate him.