In high school I saw The King and His Court (Eddie Feigner and 3 others) play an exhibition softball game at Harlan Rogers park. He struck out 20 of the 21 batters he faced, one batter managed a weak pop-up at the plate which the catcher caught. Eddie played with a catcher, shortstop, and first baseman. The reason for the two infielders was that they needed at least 4 batters in case the bases were loaded.
Eddie pitched from the mound, from second base, between his legs, behind his back, and blindfolded. According to Wikipedia:
How fast did Eddie Feigner throw?
At his peak, Mr. Feigner threw a softball harder than any major league pitcher has ever thrown a baseball. His underhand fastball was once timed at 104 mph -- or, according to some accounts, 114 mph. The fastest documented pitch ever thrown by a major league pitcher is 103 mph.