In January 1935, while playing for Nacional, Fernández helped Uruguay win the South American Championship. His team mates at both Nacional and Uruguay included Héctor Castro. He subsequently joined FC Barcelona and under coaches Franz Platko and Patrick O'Connell helped them win the Campionat de Catalunya twice and reach the final of the Copa de España. His team mates while playing for FC Barcelona included Joan Josep Nogués, Josep Escolà and Domènec Balmanya. Fernández and Balmanya made their La Liga debuts for Barça together on 10 November 1935 in a 1–0 defeat to RCD Español. He played 17 games for FC Barcelona in La Liga and scored 8 goals. Fernández scored a hat-trick against CA Osasuna in a 5–0 win on 29 March 1936 and then 2 against Athletic Bilbao on 4 April 1936. He played his final La Liga game on 19 April 1936 in a 2–2 draw against Hércules CF.