If De Gea remains at Old Trafford or Ten Hag recruits a new man between the posts, Henderson's future looks bleak beyond his stint at the City Ground.
He may also face a fight for game time under Steve Cooper once he returns from a muscular injury that has kept him out of action since January.
Forest signed PSG goalkeeper Keylor Navas on loan as a short-term fix while the England international is on the mend.
A Forest stay may appeal to Henderson if they avoid relegation in the first season back in the top flight, but any interest from Tottenham would undoubtedly turn his head.
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