In one scene, Annie calls out to her husband and daughter "Dinner!" but when he comes into the kitchen, while they're talking, she's laying out frozen french fries onto a baking dish, suggesting that she hasn't started to cook them yet. Why would she call for them to come in for dinner if it hasn't been prepared yet?
Ray has a vision of the baseball field while standing in the corn looking back at the house. In the vision, the backstop and home plate area is out in the corn, with the outfield stretching out to near the house. When he builds the field, he builds it the other way around 0 home plate and the first base line are by the house, and the outfield is in the corn. Why did the filmmakers not have the effect of the vision match the reality Ray built?
In the opening of the movie when Ray tells us he was born in 1952 then proceeds to talk of his relationship with his father, he tells us he moved away to attend college as far away as he could. Then talked of his studies, but mostly, recalled "it was remember, the '60's ". If he was born in 1952, and graduated high school at age 18, it would have been 1970 before he even enrolled in college. So he couldn't have attended college in the "60's"
At Fenway Park, when Oakland A's batter Jose Canseco is shown hitting a fly ball, the time on the scoreboard reads 8:41. A moment later, Ray looks up at the scoreboard to see the message about 'Moonlight' Graham and the time on the scoreboard reads 10:30.
During the opening voiceover, Ray states he was born in 1952, and his daughter Karen was born in 1974. Later, he states "I'm 36 years old," at the time the story starts, which would set it in 1988. However, the character of Karen is only about 5 years old in the movie. If she were born in 1974, she'd have been 13 or 14.
Toward the end when Ray and his father are playing catch, and Annie turns on the lights, Mark's jeep is no longer parked next to the light pole. But in the next shot, it reappears again in the same spot.
In one of the scenes where Ray is watching the Black Sox play at his field, Jim Doty is seen hitting a ball, and then running to first. However, when the camera shows the player on first base, it is not Jim Doty.
During their initial meeting, right after Ray and Shoeless Joe introduce themselves to each other, Joe is standing on the infield grass between the pitcher's mound and home plate with his glove on. He then jogs over to the backstop to pull some bats out of the bag. When they cut to the next shot of him jogging up to the backstop his right hand is bare and the glove is missing.
The gas station attendant in Boston tells Ray that Terence Mann lives "two blocks down, right hand side, the first door that don't have a chicken in the window is his." When Ray walks down the street, he goes into the first chicken-less door on the left hand side.
About midway through the film, when Ray and Terry leave Fenway Park, they are seen traveling "up" Landsdowne St., behind the left field wall, northbound. Landsdowne St. is a one way street headed in the opposite direction.
A player is shown in a Philadelphia Athletics uniform with a green bill on the cap, and a green colored A on the uniform. The Philadelphia Athletics team color was blue, and didn't change to green until after the franchise moved to Kansas City.
Swede Risberg is listed in the credits as the White Sox catcher brought to the field, shown in catcher's gear. Swede Risberg played short stop primarily (397 games), as well as 29 at 1st, 12 at 2nd, 24 at 3rd base, and 3 at an outfield position. He never caught even one ball behind the plate in his career.
At Fenway Park, you are not able to buy a hot dog and a beer at the same concession stand. Certain stands sell only beer (and no food other than pretzels and peanuts), while other stands sell food (including hot dogs), but no beer.
The game at Fenway Park between the Red Sox and the Athletics takes place on May 16th, because it was the only Red Sox/Athletics game at Fenway in 1988 in which Jody Reed hit first, as indicated by Ray's lineup card. The scoreboard clock says 10:32, but the actual game concluded at approximately 9:50 that night.
(Possibly deliberate on part of the filmmakers) When Shoeless Joe Jackson brings the other banned members of the 1919 White Sox to play at the field, one of them appears wearing catchers gear. None of the three players who caught games for the 1919 White Sox were among the eight players banned.
When Doc Graham is describing to Ray the extent of his playing career, he says that in the last game of the season, Giants manager John J. McGraw told him to go play right field. While the position Graham played is correct, the date is not. The last game of the Giants' 1905 season was played on October 7. Graham's only appearance with the Giants came on June 29, which was New York's 65th game of the season. They still had 90 games left to play.
Doc "Moonlight" Graham states in the movie that he was born in Chisholm, Minnesota, when in real life he was born in Fayetteville, North Carolina. However, he did die in Chisholm (although in a different year than indicated in the movie).
Moonlight Graham made his only major league appearance in 1905, not in 1922. Further, he died in 1965, not in 1972. However, in a showing of the film on AMC's "DVD-TV", it was stated that the filmmakers intentionally 'fudged' the date so that they could include the Richard Nixon gag (the "Four More Years" poster in the store window).
When Annie is discussing the mortgage with Ray, she says that they've already missed payments on the mortgage. But then she mentions later asking the bank if they can miss a couple of payments, then the bank 'sells the note' to Mark and then Mark's group demands full payment immediately. This would indicate a seriously late mortgage situation (not to mention Mark being a very dysfunctional/miserly brother) that doesn't fit the time line.
When Ray and Karin Kinsella are on the tractor mowing down the corn field in preparation for building the baseball field, the power take off shaft which should be driving the mower is not rotating which means the mower is not operating.
Ray is standing in shoulder-high corn (mid summer) when his wife calls him in for dinner as the sun sets. This would be a pretty late dinner for a farm family with a young child. Sunset would be around 9pm.
The first time Ray walks to his bedroom window to look at his cornfield, the camera closes in on him, but the perspective of the corn does not change, revealing the other side of the window to be a blue or green screen, and not a farm.