Fernandez came to Rafa Benitez Newcastle in the summer of 2018 from Swansea. The Swans had just been relegated from the Premier League and Frederico looked like a decent bit of business to cover the centre halves that had somehow guided Newcastle to 10th the season before. In fact the Argentinian International was to be more than a bit part player, making over a dozen appearances in his first season and impressing with his composure and touch on the ball.

His two goals for the club both resulted in Newcastle wins, 3-2 away to West Ham in 2019 and his second a 2-1 win over Southampton at St James Park.

He would leave after the 21/22 season with the club going in a different direction.

Capped a total of 32 times for Argentina he would play in the 2014 World Cup.