Fuentes was born in Loíza, Puerto Rico, in the barrio of Loíza Aldea. He starred as an amateur baseball player and, in 1968, helped lead his amateur team to a Puerto Rican championship. He was discovered by scoutFelix Delgado, who went on to sign Fuentes to his first professional contract.
Career with the Pilots organization
Fuentes was initially assigned to the Clinton Pilots, a Class A team in the Midwest League. He recorded an 8–2 record in 26 appearances and his earned run average of 1.46 was the lowest in the league for pitchers with 40 or more innings pitched. For his efforts, Fuentes was called to the Seattle Pilots' Major League roster in September 1969. He made his Major League debut on the first of September, striking out two in an inning of work against the New York Yankees. After a second relief appearance, Fuentes was given his first Major League start; he responded by throwing a complete game against the Chicago White Sox, giving up one run on seven hits. He made three other starts with the Pilots, with a relief appearance in between his second and third starts; in those other three starts he was credited with the loss. Fuentes ended his Major League year with a relief appearance in Seattle's final game, where he threw the team's last ever pitches, as the Pilots would become the Milwaukee Brewers in 1970. During his lone year in baseball, Fuentes compiled 1 win, 14 strikeouts, and a 5.19 earned run average.
Death
During the MLB off-season in the winter of 1969 and 1970, Fuentes played in the Puerto Rican Winter League with the Caguas Criollos. A few days after the Criollos' season ended in the league's playoffs, on January 29, Fuentes was shot three times at a bar in Loíza Aldea. "Fuentes had gone outside to relieve himself because there was a plumbing problem in the bathroom. Someone who thought Fuentes was doing it too close to his car shot him." Fuentes was sent to a hospital in a state of shock and died of his wounds shortly thereafter. Fuentes was regarded as a top prospect in the Pilots organization at the time of his death. Because of the Pilots' move to Milwaukee in 1970 to become the Brewers, Fuentes holds the distinction of throwing the final pitches in the history of the Seattle Pilots. He appears in the 1970 set of Topps baseball cards as a Seattle Pilot, as the Topps cards were already in production at the time of Fuentes' death.
