TENNIS NEWS: Federer Still Fears 'Difficult To Beat' Nadal At French Open

Swiss tennis player Roger Federer speaks during a press conference in Istanbul on April 27, 2015  

Istanbul - Switzerland's 17-times Grand Slam winner, Roger Federer on Monday said he still believed Rafael Nadal was the favourite to win the French Open next month despite the Spanish star's troubled start to the clay court season.

Federer, who took his sole French Open title in 2009, this week, is refining his own clay court game at the Istanbul Open, the first ATP World Tour event to be held in Turkey and the first time that Federer has visited the country.

But Nadal, who with the exception of Federer's win has taken every French Open since 2005 to make nine in total, has shown a dip in form over the past weeks, failing to get past the third round at last week's Barcelona Open.

Swiss player Roger Federer returns the ball to a young Turkish tennis player during an exhibition tennis match after a press conference at the ATP Istanbul Open in Istanbul on April 27, 2015 

Federer said he believed that Nadal was still the man to beat on the red clay of Roland Garros, along with the in-form Serbian world number one Novak Djokovic.

"At the French Open, Rafa for me is still the favourite alongside Djokovic who has been playing so well”."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," he told a news conference in Istanbul.

Federer, 33, is himself looking for his own form on the slower clay after a long hard court season, having lost in the third round to Gael Monfils at the Monte Carlo Masters this month. But he said the Istanbul event was ideal for his preparations.

Spain's Rafael Nadal has won nine French Open titles

"It's about getting used to the sliding, deciding how aggressive I want to play," said the world number two. "I have been on hard courts for seven-eight months so it needs some adjustments. My game is going to get better and better as we move along."

Federer, who so far has been unable to add to his sole French Open win in 2009 and won his last grand slam at Wimbledon in 2012, acknowledged that this year's French Open "is clearly a big goal of mine". "But to play well at the French Open I need confidence. I hope that I can pick that up in Istanbul."