If they would award him as easy a draw as Fedal used to almost always get as no.1, then Djokovic would make it even if blindfolded and with point penalty for every sliding on the court.Only Laver and Federer have been in all 4 GS finals during a calender year in the Open Era. Not sure how it is pre-open era, but I think it is very rare.
Djokovic has so far reached AO, FO and W final. Left is USO.
Can he do it?