The Portugal international was heavily linked with a switch to the Premier League throughout the summer, with Spurs and Manchester United among his reported suitors.
But he stayed put in Lisbon and this week put pen to paper on a new deal until 2023.
The new contract still has a release clause of €100 million, but he has agreed fresh terms that make him the club’s highest earner on €2m per season.
Sporting came to an agreement with the 25-year-old last year that if offers of over €35m were rejected, they would have to fork out €5m to the player and his agent.
The new contract was a way of the club managing to fulfil that promise without handing out a lump sum, which they couldn’t afford.
But Fernandes remains willing to leave the club as early as January and a bid of €70m could be enough to secure his signature.
Although the attacking midfielder has a release clause of €100m, Sporting have agreed with Fernandes that they will accept €70m.
Over the summer, Spurs made a bid worth €70m including bonuses, but it was turned down.
Fernandes has continued his excellent form this season, with 11 goals and eight assists in 18 appearances across all competitions.
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