During the beginning of the movie, Roger (the boy who sees angels) is up in a tree looking into the game with binoculars. At this time you can clearly see a cameraman reflected in the lenses of the binoculars.
After Toronto Blue Jay Asher Lazzato hits the fly ball that is caught by Ben Williams with the help of two angels, he appears to stop running. In a real baseball game, the batter would continue to run after hitting a fly ball.
During the Angels' game against the A's, in the bottom of the 9th, the scoreboard already shows two outs but moments later Ranch says "and with Mitchell about to lead off the bottom of the 9th, the Angels have decided to bring in utility man Danny Hemmerling."
During the first game that Roger and JP watch in the stands, when Ranch says, "So the Angels have an error and a man on base," Triscuitt Messmer can be seen in the dugout (sitting behind George Knox) even though he is actually on the field catching.
In the top of the ninth in the game against the White Sox, a sacrifice bunt moves the lead runner to second. In the next shot, the pitcher Mel Clark checks a runner at first, though there is only one man on base (at second).
When the Angels perform a triple play with the ball getting stuck in the glove, the team is wearing gray uniforms, implying an away game. However, following the play, Knox looks over to Roger and JP, while he is wearing the white home uniform at the Angel's home field.
During one of the first games shown, Whitt Bass is shown as the Angels starting pitcher. In the very next game he is also shown pitching. This is only possible if he is a reliever, but he was previously shown as a starter.
After the game against the Oakland Athletics, when Hemmeriling scores, the scoreboard is shown, constantly giving the Athletics errors, and shows the Angels have one run. In the next shot of the scoreboard, the one is now a zero.
In the last game against the White Sox there is a ground ball that the shortstop dives for in the hole. The man on second base appears to run past and advance to third on the play, but later a fly ball is caught in the outfield and the player who appeared to be on third is shown rounding third but being held up suggesting he was on second not on third.
During the game where Knox fights with Gates, Ranch is shown switching off his mic to talk to Wally about how he could be a better manager. Without switching the mic back on, he speaks into it talking about how he is curious how long the owner will put up with Knox's behavior.
At the time of filming, Anaheim Stadium was completely enclosed (to accommodate the Los Angeles Rams, whom the stadium was also home to). Aerial stock shots taken at Anaheim show an enclosed stadium, but the rest of the movie depicts an open one.
A radio announcer can be heard saying, "Welcome to Downtown Anaheim" in reference to Anaheim Stadium. The stadium, in reality, is located 3½ miles from Downtown Anaheim, in the extreme southeast corner of the city of Anaheim, on the border of the city of Orange.
On the 3-1 pitch by Mel Clark to the White Sox Hitter, Ranch says that it could be the game as the ball is headed down the Left Field Line. Since they are playing at home, the Angels hitters would have 3 outs to either tie and continue in extra innings or take the lead if White Sox took the lead in the top of the inning.
In the film, the White Sox are shown as being in the West Division along with the Angels. They are not shown to be in the East Division. As this movie was completed before the '94 season's new playoff format was enacted, one team from each the West and East division would play in the Championship series. To win the pennant, the winner of the West division must beat the winner of the east, or vice versa.
When George is about to give the boys a ride home from the game, J.P. won't get into the car because he and his mom used to live in a car and every time he gets into one, he has a stomachache. Later, after Roger's court hearing, J.P. leaps into Maggie's car with Roger without a second thought.