Early in the movie, Andie MacDowell refers to a baseball as being hit by Bill Mazeroski in the top of the ninth inning of the last game of the 1960 World Series. In fact, it was hit in the bottom of the ninth inning.
At the beginning of the movie when the boy catches the Mazeroski home run that won the 1960 World Series, it was a Rawlings baseball. Rawlings did not begin supplying baseballs to the major leagues until around 1970. The home run ball would have been a Spalding baseball in 1960.