The winger had hip surgery late last year after an injury-hit start to the season.
Fernandez tweeted in November: "This start of the season has been complicated, with some problems that have finally made me go through surgery.
"I have had an operation in the hip, but luckily everything went very well, and I am already thinking on recovering as soon as possible to play again."
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Fernandez has since recovered from the operation.
And the 21-year-old took part in today's first-team training session at Newcastle's Benton HQ ahead of Sunday's season-ending Premier League fixture against Fulham at Craven Cottage.
Meanwhile, Fernandez's Under-23 team-mates take on Everton at Goodison Park in the final of the Premier League Cup.
Fernandez – who made his senior debut in last season's friendly against Royal Antwerp in Spain – has been restricted to just one appearance for Ben Dawson's side this season because of injury.