Just from quickly looking it up, from what I can see, Markieff Morris has been on-and-off one of the better combination defenders as a pick-and-roll defender, iso defender, and postup defender over the last 5 seasons. He struggles in a year in one of the categories while the others are good, but as a whole, I could definitely see how getting him in a consistent role in a good system could potentially turn him into an under-the-radar juggernaut defensively.
Plus, he just saw how CBS got his brother a big fat paycheck. He would have to be motivated.