Nadal:8 years 2W, 1AO & 1 UO ....... how many can he win in next 4 ?
sure he has at least 3 more RG in him, but not many of other 3 GS.......
djoper can win few more[ 4-5] but he had that dry spell after winning 1st AO .....
Fed is done

, so Somebody else must [or not] step up and for me that is real question :
"Can somebody else prevent Rafa/djoper from winning everything"
ps
djoper saved Feds record [for now] by taking 3 titles from Rafa last year,
Fed saved Rafa by beating djoper last year in RG semis,
Rafa saved Fed by preventing djopers 4 in row slams [all time the best argument] .....