Difference between Crackpot and Screwball

What is the difference between Crackpot and Screwball?

Crackpot as a noun is an eccentric, crazy or foolish person. a kook. while Screwball as a noun is a pitch thrown with added pressure by the index finger and a twisting wrist motion resulting in a motion to the right when thrown by a right-handed pitcher.

We hope you now know whether to use Crackpot or Screwball in your sentence.