Roger Federer and Rafael Nadal
Rafael Nadal (L) of Spain and Roger Federer of Switzerland hug at the net, after Nadal won their men's singles semi-final match at the Australian Open 2014 tennis tournament in Melbourne January 24, 2014. REUTERS/Bobby Yip REUTERS/Bobby Yip

Before the 2015 Wimbledon Championships went into full swing, seven-time Swiss champion Roger Federer took time out to speak with CNN’s Christiane Amanpour where he talked about a number of things, including the toughest opponent that he has ever faced on tour. According to Federer, Spanish tennis ace Rafael Nadal is the toughest opponent that he has battled in his career.

“Probably, Nadal, just because of his playing style, he is a leftie as well, that makes things more complicated,” Federer said. “Plus, we’ve had a lot of matches on clay where he reigns supreme, he’s the best ever on clay, hands down, so he has been the toughest and probably the most challenging and fun to play against just because of his character and he’s been unbelievable for the game so I love that rivalry.”

Federer and Nadal’s rivalry started all the way back in 2004 in the third round of the Association of Tennis Professionals Miami Masters event. He upset Federer, who was then World No. 1, in straight sets. The Swiss trails in their head-to-head series 10-23. The Spaniard had won in their last five meetings, with their most recent that occurred in the semifinals of the 2014 Australian Open.

Twenty of their 33 professional matches took place in the finale of grand slam tennis events and 1000 series tournaments. Federer had only six in those final matches. In the finale of grand slam tournaments of the 2008 and 2009 season, Federer and Nadal met three times, with the Spaniard winning in all those events (2008 French Open, 2008 Wimbledon, and 2009 Australian Open).

Federer is through to the quarterfinal round of the 2015 Wimbledon Championships where he will face Gilles Simon. The 17-time Swiss grand slam champion is bidding to win an eighth Wimbledon title, which he last won in 2012. Since then, Federer has not won a grand slam. Nadal, on the hand, had an early exit in the tournament after falling to the hands of German qualifier Dustin Brown in the second round 7-5 3-6 6-4 6-4.

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