Rafael Nadal’s struggles at the start of the clay-court season may see the Spaniard in the unfamiliar position of going into next month’s French Open as something over than the favorite, but his great rival Roger Federer believes the Spaniard will still be the man to beat in Paris. Nadal was beaten in straight sets by world No. 1 Novak Djokovic in the semifinals of the Masters 1000 event in Monte Carlo earlier this month before a shock loss to Italian Fabio Fognini in Barcelona further derailed his preparations to attempt to land a 10th French Open title.

It had already been a poor start to 2015 for Nadal. Returning after injury blighted his second half of last season, Nadal has won just a relatively minor clay-court event in Buenos Aires in February and, though ranked fourth, is only eighth in race to London, based on results this year. Most worryingly, the return to his favored surface has not yet yielded the upturn in results many anticipate.

Speaking on his home island of Mallorca on Thursday, Nadal stated that he was determined to return to his best and convinced that he will do so. Yet he also suggested that it should not be surprising that after so long at or near the top of tennis he has suffered a blip.

“Even Bjorn Borg could not win for 20 straight years and Federer has also spent periods that have not been so good, the biggest in the history of the sport are not eternal,” he said, reports Spanish publication AS.” I am not either. I don’t know how long success will last, I didn’t know in 2005, or in 2006, or 2008.”  

And there is cause for Nadal not to be overly perturbed by his poor start on clay. Last year he also struggled on the surface, relative to his own unparalleled standards, and it was the first time that he had registered three losses in the clay-court season heading into Roland Garros. Yet when it mattered Nadal still took the home an unprecedented ninth title. Nadal has only ever lost once at the French Open and he has beaten his biggest challenger, Djokovic, in each of the previous three years. And Federer, the man who took the French Open title in 2009 after Nadal’s defeat to Robin Soderling, believes it would be foolhardy to write the left-hander off.

“At the French Open, Rafa for me is still the favorite alongside Djokovic who has been playing so well,” the Swiss said, according to AFP. “Even though his [Nadal's] form is not as good as in previous years, I still believe when the French Open rolls around he is going to be very difficult to beat,”

Federer has his own ambitions going into Paris. The 33-year-old lost early in Monte Carlo, to Gael Monfils, but he will certainly be eager to get past the quarterfinals for the first time since 2012. Federer is in action in Istanbul this week before heading to the prestigious Masters 1000 event in Madrid. Nadal will also be in the Spanish capital, aiming to kick-start his season and retain the title he won by beating Kei Nishikori in the final last year. For Nadal, his results ahead of Paris will now be key as he looks to stave off the threat of Nishikori taking his No. 4 ranking and leaving Nadal with a potential matchup with Djokovic as early as the quarterfinals at the French Open.