Sergio Reguilon is one of the best young full-backs in the world. The Real Madrid academy graduate is garnering interest from up to 10 different clubs across Europe according to ABC Deportes. The clubs interested include Arsenal, Tottenham, Borrussia Dortmund, PSG, and Sevilla. As Ferland Mendy’s agent indicated last year, top quality left-footed fullback’s are a rare commodity in the transfer market.