It Happens Every Spring is a 1949 American science fiction sports comedy film directed by Lloyd Bacon and starring Ray Milland, Jean Peters and Paul Douglas.

A college professor is working on a long-term scientific experiment when a baseball comes through the window, destroying all of his glassware and spilling the fluids that the flasks and test tubes contained.

The pooled fluids combine to form the chemical "methylethylpropylbutyl," which then covers a large portion of the baseball.

Suddenly, he realizes the possibilities and takes a leave of absence to go to St. Louis to pitch in the big leagues, where he becomes a star and propels his team to the World Series.

[2] New York Times critic Bosley Crowther found the film trying, particularly Valentine Davies's "monotonous" script.