it seemed like Djokovic was more aggressive in sets 1, 2 and 3.
Set 4 it looked like Djokovic's shots were low velocity and barely clearing the net.
this was presumably because Djokovic was falling into the trap of treating Murray like an injured opponent, and just moving Murray around.......and instead Djokovic's shots kept falling into the net, or were landing around the service box which Murray put away
At 5-4, after several easy holds by both players, Djokovic finally got the break to win the match when Murray did what he's done all year and threw in consecutive errors at a crucial time.
but i hate to see players play passive when the opponent is injured.
Wawrinka made that mistake in the AO final versus Nadal and it cost him the 3rd set

but on that occasion Wawrinka woke up in the 4th set and regained his aggression for the win.