Miguel "Sugar" Santos (Perez Soto) spends his weekends at home, passing from the landscaped gardens and manicured fields on one side of the guarded academy gate to the underdeveloped, more chaotic world beyond. In his small village outside San Pedro de MacorĂ­s, Miguel enjoys a kind of celebrity status. His neighbors gather to welcome him back for the weekend; the children ask him for extra baseballs or an old glove. To his family, who lost their father years before, Miguel is their hope and shining star. With the small bonus he earned when he signed with the academy some time ago, he has started to build his family a new houseâone that has a bigger kitchen for his mom and a separate room for his grandmother.
After learning a devastating knuckle curve, Sugar is invited to spring training by the fictional Kansas City Knights. He is assigned to their Single A affiliate in Iowa, the Swing. He is housed by the Higgins family, who take in Swing players every year. Jorge (Rufino), a veteran player and the only other Dominican on the team, also tries to help Miguel learn the ropes. However, despite the Higgins' welcoming efforts and Jorge's guidance, the challenge of Miguel's acceptance into the community is exposed in small ways every day, from his struggle to communicate in English to an accident of casual bigotry at a local bar.
Miguel's domination on the mound masks his underlying sense of isolation, until he injures himself during a routine play at first. While Miguel is on the disabled list, Jorge, his one familiar connection to home in this strange new place, is cut from the team, never fully regaining his ability following off-season knee surgery. The new vulnerability of Miguel's injury, coupled with the loneliness of losing his closest friend, force Miguel to begin examining the world around him and his place within it. Pressure mounts when Salvador, a young pitching phenom who used to play with Miguel, is brought up from the Dominican Republic to join the team. Miguel's play falters, and the increased isolation begins to take its toll on him. As his dream begins to fall apart, Miguel decides to leave baseball to follow another kind of American Dream. His odyssey finally brings him to New York City, where at first he struggles to find community and make a new home for himself, like so many before him. Miguel ends up playing baseball with rejected players from the minor leagues.

Question: What begins to take its toll on Santos?
Answer: His increased feeling of isolation.
Alternative answer: Isolation.