Exclusive - Liverpool, Manchester United, Manchester City and Tottenham Hotspur have all been hugely impressed by the recent emergence of Schalke striker Matthew Hoppe.
Thrown in at the deep end to try and save a Schalke side who are rooted to the bottom of the Bundesliga, the 19-year-old American has responded with five goals in just eight league starts, earning himself his first professional contract early in February.
Hoppe has already climbed his way to the top of the struggling team's scoring charts, and sources have confirmed to 90min that clubs from across Europe have started to take notice of the American's exploits.
Scouts from Liverpool, United, City and Spurs have been monitoring Hoppe's development and all have been impressed with what they have seen, while clubs in both Italy and Spain have also been checking in on the teenager.
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One source with knowledge of the situation explained to 90min that Hoppe's form and progress has caused a real stir among Europe's biggest clubs, many of whom are confident they would be able to sign the teenager if they tried.
The belief is that Schalke could be forced to sell Hoppe this summer, namely because they are cut adrift at the bottom of the Bundesliga, but also because financial difficulties may force their hand.
Schalke found themselves with debts of close to £175m even before the COVID-19 outbreak crippled football's finances even more, and the belief across Europe is that they could be forced to hold a fire sale this summer to try and stay afloat.
Valuable assets like Weston McKennie and Ozan Kabak have been allowed to leave on loan this season in the hope that they seal permanent moves to Juventus and Liverpool respectively, and interested teams could try and make Hoppe the next player to leave the Veltins-Arena.
There has also been murmurs of interest in fellow young stars Suat Serdar and Amine Harit, the latter of whom came close to joining Villarreal in the January transfer window.
Schalke have no desire to part ways with Hoppe or any of their young core, but the fear is that they may be left with no choice but to sell.