Federer won the Halle Open title in the build-up to the British Grand Slam and will feel right at home when his campaign gets underway on Tuesday.
However, Djokovic opted to not play a grass ATP event prior to Wimbledon, instead electing for an exhibition event in Stoke.
Rafael Nadal also followed suit, but he trained at the Mallorca Open and Hurlingham.
Rusedski can only see one of the top three players in the world winning Wimbledon.
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But he fears for world No 1 Djokovic because of his limited preparations.
“I think a certain guy by the name of Roger Federer [is the favourite to win Wimbledon], who a lot of people have heard of,” Amazon Prime pundit Rusedski told Express Sport
“He impressed me at the French Open and all this year.
“It is coming from the Big Three. I think Federer, Rafa [Nadal]- Novak I’m a little concerned about.
“The defending champion didn’t play a [ATP] tournament.
“He played a few exhibition matches and then will play the Wimbledon Championships.”
Youngster stars have come to the fore in recent years – although they have yet to prove their Grand Slam pedigree.
Alexander Zverev, Stefanos Tsitsipas and Felix Auger-Aliassime, to name a few, are expected to take over from Federer, Nadal and Djokovic when they retire.
But Rusedski feels they are not yet quite ready to win a major tournament.
“But I see the winner coming from Roger, Rafa or Novak,” he added.
“I am not sure Tsitsipas or Auger-Aliassime are quite ready against those three. Ask me the question next year and it might be a different answer.”
Wimbledon commences on Monday, July 1 with the final due to take place on Sunday, July 14.
