#2 Frenkie de Jong (Ajax)
Frenkie de Jong is another very interesting player worth Barcelona considering as Busquets' long-term successor. The 21-year-old Dutchman is a generational talent who has all the abilities needed to become a legend in the game.
One of his best attributes in getting the ball from defence into midfield quickly, a great asset for modern-day defensive midfielders. He has the technical skillset to orchestrate play well, while he's calm on the ball, rarely makes mistakes and is consequently a joy to watch.
Many top European sides have been monitoring his progress and it appears likely that he'll finally make a move once the current campaign is concluded next year - Premier League champions Manchester City are among those thought to be heavily interested. It will be tough for Barcelona to sign him given just how much interest there is over his services, but nothing good ever comes easily, so it'll be interesting to see who the lucky beneficiaries are.