A disciple of magic tank I don't exactly expect.

A disciple of magic melee DPS? Sure. As mentioned Red Mage - or even whatever they adapt Blue Mage into could fit in this (Given that most monster skills are user-based AoEs it could actually make sense).

Realistically I can see it having issues (Melee characters usually have to move more than mages, cutting out cast time; a melee caster would be locked out of autoattacking; and a few others), but it could be made to work.