Djokovic/Nadal/Federer/Sampras : CYGS/NCYGS/Career Grand Slam/Calender Year Clay Slam/Career Clay Slam/
Season Opening Hard Court Hatrick (AUS/IW/Miami)/US Summer Hardcourt Hatrick (Canada/Cincinnati/USO) /Year End Indoor Court Hatrick (Shanghai/Paris/WTF) :-
Djokovic :
CYGS = 0
NCYGS =
+1 (+ one close miss by 2 sets)
Career Grand Slam = achieved =
+1
Calendar Year Clay Slam = 0
Career Clay Slam = achieved =
+1
Season Opening Hard Court Hatrick (AUS/IW/Miami) =
+3 (2011-2015-2016)
US Summer Hardcourt Hatrick (Canada/Cincinnati/USO) = 0
Year End Indoor Court Hatrick (Shanghai/Paris/WTF) =
+2 (2013-2015)
TOTAL = PLUS
EIGHT
Nadal :
CYGS = 0
NCYGS = 0 (one close miss, by 3 matches)
Career Grand Slam = achieved =
+1
Calendar Year Clay Slam =
+1 (2010)
Career Clay Slam = achieved =
+1
Season Opening Hard Court Hatrick (AUS/IW/Miami) = 0
US Summer Hardcourt Hatrick (Canada/Cincinnati/USO) =
+1 (2013)
Year End Indoor Court Hatrick (Shanghai/Paris/WTF) = 0
TOTAL = PLUS FOUR
Federer :
CYGS = 0
NCYGS = 0 (two close misses, by 2 sets, X 2)
Career Grand Slam = achieved =
+1
Calendar Year Clay Slam = 0
Career Clay Slam = 0
Season Opening Hard Court Hatrick (AUS/IW/Miami) =
+1 (2006)
US Summer Hardcourt Hatrick (Canada/Cincinnati/USO) = 0
Year End Indoor Court Hatrick (Shanghai/Paris/WTF) = 0
TOTAL = PLUS TWO
Sampras :
CYGS = 0
NCYGS = 0 (one close miss, by 3 matches)
Career Grand Slam = 0
Calendar Year Clay Slam = 0
Career Clay Slam = 0
Season Opening Hard Court Hatrick (AUS/IW/Miami) =
+1 (1994)
US Summer Hardcourt Hatrick (Canada/Cincinnati/USO) = 0
Year End Indoor Court Hatrick (Shanghai/Paris/WTF) = 0
TOTAL = PLUS ONE
Novak is ahead...Even if you add the other three together...


Having said that; the Calendar Year Clay Slam, is by a long way the hardest Masters/Slam combo because it involves four tournaments whereas the other Masters/Slam or Masters/WTF combos involve three tournaments
Nadal is the only player in the Open Era to achieve The Calendar Year Clay Slam and one of only four players in the Open Era to have completed The Career Clay Slam :
Vilas/Lendl/Nadal/Djokovic
The US Summer Hardcourt Hatrick has only been achieved three times by : Rafter in 1998, Roddick in 2003, and Nadal, (again), in 2013