World's No. 7 Swiss Professional Tennis Player Roger Federer had a disappointing 2013 season. What could be worse to end the season with a defeat to World's No. 1 Rafael Nadal?

People have noticed that the 2013 season is Federer's least successful year. Many believed that his career seems to have gone on a steady decline. This season is the first time that he had not reached a Grand Slam since 2002.

On Sunday, Federer lost to Rafael Nadal in the semi-finals of the Association of Tennis Professionals (ATP) World Tour.

"Very rarely, I go through matches where I had no opportunities," Federer said. "Today's game was a little bit more of making or missing your opportunities, and I thought that the margins were more on Rafa's side," he added. "Rafa was playing more consistent and more solid, and I just couldn't come up with the shots when I needed them most, either forehand or serve," he noted.

The Swiss athlete has only won once against the Spanish, whom he had met for four times in 2013.

Is Federer going to retire soon? Currently, he is the oldest player in the tournament at 32.

"The thing is that when you stop, you are still young," Federer said. "So, why stop early," he added. "I can still decide, and I chose to play so as long as I have this choice, I will keep on playing," he noted.

"I believe that I had a strong finish in Basle, Paris, and London," said Federer. "I feel more positive than I was several months ago," he said. "I feel confident moving on to the off-season, but it is significant that I stay within a certain ranking while making sure than I also stay spirited," he said. .

For many athletes, it is difficult to imagine the day in which they will retire. Surely, it is an athlete's greatest challenge. As for Federer, we wouldn't worry about it because we will be seeing more of him as long as he has the drive and enthusiasm to compete.

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