yes and no. Fullbacks, wingbacks, inverted wingbacks, defensive full backs, whatever you like to call them. Gets oversimplified sometimes. I think its a position that requires a lot of understanding of tactical positioning. Full backs are expected to push up and overload the opposition, not just on the wings these days, but also to move into the middle, like Johan Neeskens? Of course it depends on how sophisticated the tactics you are employing. I read an article before that says Guardiola has spent the most amount of money on fullbacks.