Roger Federer has paid tribute to his "chief rival" Rafa Nadal.
The Swiss tennis player has said he would not be as successful were it not for Nadal.
Nadal has a winning record against Federer but the majority of those victories occured on clay, a surface Federer decided to take a break from this year.
The French Open, the clay major, takes place without Federer on Sunday — but it remains a competition he hopes to return to in the future.
Roger Federer has said that he would not be...