He can be developed into the sort of defender who wins most headers, clears his lines without taking risks and focuses on keeping things simple. Problem is, that’s not really the sort of defender that is effective in Thelin’s system.
We need defenders who are comfortable on the ball, both in terms of passing and keeping possession in tight areas. The type of defender that will be comfortable playing in midfield. That’s never going to be Rubezic.
You can see the difference in MacDonald looking solid playing in a Robson team and looking like a fish out of water playing for Thelin.