The legendary duo, aged 36 and 31 respectively, are still dominating the sport despite being in the latter stages of their career.
The pair have won all five of the last five Grand Slams with Nadal the short-priced favourite to make it six at the French Open next month.
However, the Spaniard was downed by Dominic Thiem at the Madrid Open while Alexander Zverev and Denis Shapovalov have also impressed.
Sky Sports pundit Rusedski thinks it is too early for the domination to be broken this year but it could be a different story in 2019.
He said: “You have got to remember that Denis Shapovalov is 19 years of age. I can’t remember a 19-year-old with that sort of mentality already.
“It just shows you the potential that this youngster has.
“It’s almost like the new generation is starting to feel it’s way up. It’s like they’re thinking ‘we can’t have Federer, Nadal, Murray and Djokovic transforming the sport’.
“It’s like there’s a bit of transition going on. Are they ready to take over from those two or four guys?
“I don’t think so, not quite the moment, but maybe they can in 2019.
“I am hoping that one of them surprises us all and wins a major and does something special as it would make such an impetus to this game.”