The Serb's astonishing form during a 37-0 start to the year, including consecutive victories on clay for Djokovic over the world number one, means that for the first time since 2005 Nadal is not the overwhelming favourite for the claycourt slam.

Since Nadal first bounded on to the scene with muscles bulging from his cut-off shirts and pirate shorts he has, for all but one match, looked unbeatable on Parisian brickdust.

Every challenge thrown his way was answered in emphatic style as he stormed to five titles with a win-loss record of 38-1, the sole defeat coming in an injury-hit 2009 against Sweden's Robin Soderling when his body betrayed him.

With Borg's record looming, however, Djokovic looks to have erected a barricade that even Nadal's formidable claycourt armoury suddenly looks ill-equipped to dismantle.
Successive victories over the Majorcan powerhouse in the finals of the Madrid and Rome Masters, having never beaten him on red dirt before, have changed the lay of the land.

In Rome, in particular, there were times when Djokovic appeared to have Nadal on the end of a piece of string, pulling him one way and another to his heart's content. John McEnroe, the former world number one and seven-times Grand Slam champion, thinks Nadal must go back to the drawing board in search of a new strategy.

“I think the way he approaches matches against Djokovic he is going to have to think about changing some of the ideas he had before the last couple of matches,” McEnroe, whose record 42-match win streak from the start of the year ended in the French Open final in 1984, told reporters this week.

“He has to take a few more chances, get Djokovic on the defensive a bit more, instead of letting Djokovic dictate play and banking on him missing.

“It seemed like he got pushed around a bit (in Madrid and Rome) and I'm sure his camp will go back to the drawing board.

“Nadal came off one of the greatest years in Open tennis history and now all of a sudden he finds himself befuddled and baffled at what to do when he plays against Djokovic.”

With Djokovic and Nadal hogging the limelight ahead of the French Open, 2009 champion Roger Federer, finds himself in the rare position of arriving for the start of a Grand Slam as an “outsider” although the Swiss will still be dangerous.  Last year the 16-times Grand Slam champion was overpowered by eventual runner-up Soderling in a damp quarterfinal tussle and his claycourt preparations this year have included defeats by Juergen Melzer and Richard Gasquet.

Australian Open runner-up Andy Murray could also come into contention while Soderling, runner-up for the past two years, and Spain's David Ferrer will fancy their chances.

Wide open

Meanwhile, in the women’s draw, trying to pick a winner is like trying to get a ticket for the final -- nearly impossible.

Rarely could there have been a more wide open Grand Slam with world number one Caroline Wozniacki, last year's winner Francesca Schiavone, injury-troubled Kim Clijsters and suddenly resurgent Maria Sharapova all in with a shout.

Equally, they could all crash out in the early rounds on the Roland Garros clay as such is the splintered nature of women's tennis at the moment.

With Venus and Serena Williams still ruled out with injury and Dinara Safina taking an indefinite break from the game, absolutely anything could happen, like Italian Schiavone’s triumph last year.

Germany's Julia Goerges stunned Wozniacki to win the Stuttgart title last month and then got to the Madrid semifinals before losing to in-form Victoria Azarenka of Belarus, another potential winner.

Wozniacki -- top-ranked but still to win a major -- is creaking under the weight of the millstone round her neck and although she won her first claycourt tournament of the year in Charleston, the Dane has stuttered since. Sharapova, yet to win the French having claimed the other three Grand Slams, has suffered a string of injuries but routed Wozniacki in the Rome semifinal last week before beating last year's Paris runner-up Samantha Stosur in the final. Her uncompromising streak underlines her newfound confidence having almost disappeared from many fans' radars. World number two Clijsters might have been a clear favourite for the title two months ago but after suffering injuries, the Belgian is struggling to be fully fit.