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It has become part and parcel of football to spot a young, prodigious talent and begin imagining the feats they might achieve. Alexander Isak is the next Pierre-Emerick Aubameyang, Romelu Lukaku was the next Didier Drogba...positive comparisons fuel positive narratives, and we latch onto them as football fans.

But sometimes careers don't go to plan. Even at 20 or 21 years of age, alarming slides can occur and players' stocks can fall through the floor. That, sadly, is the focus of this article: players who have promised so much, yet in 2016-17 have taken at least one step backward.

Only players who will be 21 or younger by June 1, 2017 are eligible, and the players are ranked in accordance with how far they've fallen.