Steve Nebraska's character is loosely based on a pitcher named Steve Dalkowski. But, unfortunately he never made it to the major leagues.
When Steve Nebraska is pitching in front of Baseball Scouts at Yankee Satdium, during filming Keith Hernandez walked out of the dugout wearing Tennis Shoes, and Yankee owner George Steinbrenner told Henandez to put on spiked Shoes so he doesn't mess up the grass.