Nadal can play 1/2 season a year for another 5 years.
Nole will never get back to 2011 level, but he can still win a few more slams.
Hopefully, Murray still has some gas left in his tank but he has already wasted so many years before winnng his first slam. I doubt that he will make 8 USO final as his coach.
Possibly Fed will be the last person to retire??