I really doubt you see ANY adjustments from either coach.
One, what happened at the end of the game was that the Magic started playing better defense and the Celtics lost focus. All Doc needs to do is to tell the team to keep doing what they were doing and to remember it' a 48 minutes game and not to lose focus. No personnel or system or rotational or minutes changes or adjustments will occur. Doc will just stress to give a better 48 minute effort.
Two, the Magic came out unfocused, unprepared for the Celtics' intensity and didn't give the required mental effort to match the physical one they brought. Simply put, Van Gundy will stress to trust the system, to match intensity with intensity and focus more. Unless Barnes is really hurting I doubt any changes will be forthcoming from the Magic either as, simply put, the Magic didn't play Magic basketball well yet in this series. When they do and if the team is still failing, then adjustments will come.
But seriously, no coach is going to be making adjustments after game one of a 7 game series, especially when one team came and played their game and the other didn't come and play their game.