The Argentinean centre-back has slipped down the pecking order at St James Park following the arrivals of Dan Burn and Sven Botman over the last two transfer windows.
Club captain Jamaal Lascelles remains a key part of Eddie Howe’s plans and Swiss defender Fabian Schar was rewarded with a new deal this summer after playing a lead role in the club’s surge up the Premier League table throughout the second half of last season.
That has left Fernandez to watch on from the sidelines and the 31-year-old has not appeared in a Premier League fixture since he came on as a late subsitute in a 1-0 win against Burnley last December.
United boss Howe spoke about his battle back to fitness in pre-season, saying: “Fede has picked up a minimal calf injury. It’s tight but we’re taking it carefully to build him back up before he trains.
“Fede, as I’ve said many times, is one of the leaders of the group - a very positive influence around the players so I’m delighted he’s here. We hope to get him back on the pitch as soon as possible.”
His absence has led to speculation he could be allowed to depart ahead of Thursday’s transfer deadline and one report has suggested Stoke are ready to make a move for his services.
Journalist Alan Nixon has suggested the Potters are trying to identify how much of Fernandez’s reported £60,000-a-week salary they would have to pay to allow Eddie Howe to part company with the defender on a temporary basis.