The 20-year-old burst onto the scene with the Bundesliga club when he scored a hat-trick in 4-0 win over Hoffenheim in January.
However, that was Schalke’s only win of the season so far and Hoppe looks almost certain to leave with the historic German club looking destined for the drop.
Schalke have picked up 10 points all season and sit bottom of the table, 13 points away from the relegation play-off spot.
According to AS, Valencia have been tracking Hoppe’s progress and hope to sign him on favourable terms if Schalke are relegated.
However, La Liga rivals like Villarreal, Sevilla and Barcelona have also sent scouts to follow the American’s progress.
Hoppe, who has scored five goals in 16 Bundesliga appearances this season, has previous ties to the Catalan club, having come through the Barca Academy based in the USA before moving to Germany in 2019.
But Spurs, PSV and Ajax have already contacted the player about a potential summer switch, setting up a possible bidding war.
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