rozier and smart couldn't have a better mentor than isiah for tricks in the paint,drawing fouls,change of pace,timing,change of direction-rosier will pick up things he's never seen and with his speed ,burst and vertical will eclipse marcus in certain areas in the paint
marcus has that strength and length and power that comes with his frame
rozier has smart and bradley to teach him the tricks and trade of nba defense
also the ref's let the celtics play a tough d-that is just expected,so that should give him the ability to play tough and tight without those cheap rookie fouls-
i just re watched isiahs tapes,he is a genius in his ability to attack and frustrate as well as getting the crowd excited-his ability to draw fouls and force lineup changes hampering the other teams defence and continuity,just the amount of attention needs from hitting three's and pick and roll benefits everyone
rozier has a chance to learn from isiah and with his extra hieght , wingspan and nature to play tough d -rozier could not have wound up in better place with the perfect coach