“St. Joe was playing Denver at St. Joe in the Western League. There were a lot of cowboys on hand who had bet on the game,” the Brooklyn Daily Eagle reported. “Each carried a couple of pistols. The score was tied and the home team loaded the bases in the ninth with two out. The batsman raised a tall fly ball to center field. The outfielder was camped under it when these cowboys whipped out their guns and shot the ball into bits.”
The rest of a great article is here:
https://www.fangraphs.com/tht/the-mo...eague-history/