He enrolled at Braulio Alonso High School in Tampa, Florida, and was selected by the Marlins in the first round of the 2011 MLB draft.

Fernández and two other men were killed in a pre-dawn boating crash into a jetty off the coast of Miami Beach, Florida, on September 25, 2016.

Fernández grew up in Santa Clara, Cuba, where he lived on the same street as his friend and future Major League Baseball (MLB) shortstop Aledmys Díaz.

[3] They played for the same youth baseball team, and Díaz's father and uncle encouraged Fernández's mother to bring him to the ballpark.

Fernández commented that he pursued a professional baseball career because Díaz's uncle had been an influence early in his life.

[9] Playing on the high school baseball team, José was part of the Florida Class 6A state champions in his sophomore and senior seasons.

[10] Before his senior year in 2011, the Florida High School Athletic Association ruled that Fernández was ineligible,[clarification needed] as he entered the ninth grade while in Cuba in 2006 and had therefore exhausted his eligibility.

[13] Pitching for the Greensboro Grasshoppers of the Class A South Atlantic League (SAL) to start the 2012 season, Fernández threw the first six innings of a combined no-hitter.

[15] After pitching to a 7–0 win–loss record and a 1.59 ERA in 14 games for Greensboro, the Marlins promoted Fernández to the Jupiter Hammerheads of the Class A-Advanced Florida State League.

However, they chose to add Fernández to their 25-man Opening Day roster, due in part to injuries to Nathan Eovaldi and Henderson Álvarez.

[19] Also, Marlins owner Jeffrey Loria hoped that promoting Fernández would buy him goodwill with the fans, following a fire sale the previous offseason.

[29] He followed up his July by compiling a 1.15 ERA with 49 strikeouts in 39 innings pitched in August, which resulted him in receiving a second consecutive Rookie of the Month Award.

[40] Fernández recorded nine strikeouts while walking none, and he joined Bob Gibson, Steve Carlton, Ferguson Jenkins, Walter Johnson, and Cy Young as the only pitchers to do so on Opening Day.

An MRI revealed that the elbow had a torn ulnar collateral ligament, which prematurely ended Fernández's 2014 season.

[49][50] To aid his recovery from Tommy John surgery, Fernández cut back on the use of his fastball during spring training in 2016 and began working on his secondary pitches.

[51] Appearing as a pinch hitter in the 12th inning against the Atlanta Braves on July 1, Fernández doubled in two runs to put the Marlins ahead 7–5, which ended up being the final score.

[63][64] Fernandez married Alejandra Baleato Marichal, his high school sweetheart, in December 2012 in Tampa, Florida.

[66][67] On September 20, 2016, five days prior to his death in a boating accident, Fernández announced that his girlfriend Maria Arias was pregnant with their child.

Strange-Gordon paid tribute to him on the day after his death by wearing Fernández's batting helmet and standing in the right-hand batter's box for the first pitch from Mets' starter Bartolo Colón.

[71][74] A Florida Wildlife Commission (FWC) official confirmed that Fernández had died from the blunt impact of the crash.

[76] On October 28, 2016, ESPN obtained the autopsy and toxicology reports, which determined that Fernández had cocaine in his system and was legally drunk (DWI) at the time of the crash.

[70] Teams around the major leagues honored Fernández, paying tribute with a league-wide moment of silence and the display of his jersey No.

[79] The next day, all players wore his jersey for the final time for that night's game, a 7–3 win over the New York Mets.

[83][84] In February 2017, the families of Eduardo Rivero and Emilio Jesus Macias sued Fernández's estate for $2 million each, claiming negligence and personal injury.

[90] Prior to the investigative report, there had been talks about honoring Fernández with a statue, streets named after him, and plaques throughout the city.