There is a good chance for Murray to defeat Djokovic in best of 3 sets. But the Olympic final might be played for best for 5 sets. There is a high probability for Djokovic to make it a golden slam this year and if he goes on to break Fed's record of 17 GS titles, then he can be regarded as the GOAT..... Fed mananged to win only 1 slam after 29 years age... so it will be interesting to see how many slams Djoko manages to win, now that he is 29.