What is the main conflict in Dominoes by Jack Agueros?

"Dominoes" is about four Puerto Rican men who are playing a game of dominoes on the sidewalk in East Harlem (also known as Spanish Harlem), the Puerto Rican community of New York City. A violent quarrel suddenly erupts, leaving one man dead and another maimed for life. The story is notable for the insight it gives into aspects of Puerto Rican culture, such as the concept of machismo; it also has an underlying philosophical theme of fate versus free will. Stylistically, "Dominoes" is notable for its sharp, vivid images, and its deft portrayal of characters with just a few telling details.