For the first time in his career Nadal lost three matches on clay in the build-up to Roland Garros, which he has ruled in eight of the last nine years.
With Djokovic being one of those conquerors, in last weekend's Rome Masters final, several pundits have tipped the Serb to win the tournament.
British bookmakers William Hill also have Djokovic as a 5/4 favourite ahead of Nadal (13/8).
Federer's money, though, is on Nadal.
"Not different to previous years," Federer, champion in 2009, told a news conference after easing into the second round on Sunday.
"(Nadal) is back on where he wants to be.
"He's played his matches he needs to play. He's even won one of the, one of the Masters 1000 in Madrid. So I think he probably is where he wants to be, in my opinion."
Nadal admitted to nerves earlier this season but he has said that he is feeling better as he looks to improve his 59-1 record at Roland Garros.
Djokovic, who has never won the French Open, has also been hampered by a right arm injury in the run up to Paris.
Asked if he thought Djokovic was the favourite given his recent form, the 17-times grand slam champion quipped: "Not for me, but maybe for you.
"And three weeks ago he couldn't play tennis anymore, I remember that too. When he was injured, oh, my God... things are looking so terrible. Now everything is great.
"It doesn't go week by week. I don't know who's talking all the time, but Rafa is the favourite, and then Novak, and then the rest. It's very clear."
Nadal will start his campaign against American Robby Ginepri while Djokovic will take on Portuguese Joao Sousa.
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