Rafael Nadal's Lesser-Known Threats at 2013 French Open

Rafael Nadal is once again the favorite to win the French Open, although earning his eighth career win will not be easy.

The good news is that the list of regular contenders is less of a threat than usual. Andy Murray withdrew from the tournament due to a back injury. Novak Djokovic has struggled with ankle issues and has lost early in each of the last two events.

While Roger Federer is always a tough player to beat, Nadal easily defeated him in the finals of the Rome Masters, 6-1, 6-3. This might be a better match on another surface, but the Spanish star owns the rivalry on clay. 

This leaves a batch of lesser-known stars to do what it takes to beat the defending champion. While it would be an uphill battle, these players have what it takes to pull an upset.

David Ferrer

Tennis folks know all about David Ferrer, but he's not a common name to those who just watch the Grand Slam events. However, the veteran continues to get better in these tournaments and has reached the semifinals in three of the last four.

The Spanish player has two tournament titles this year and is especially good on clay, where he holds a 71.1 percent winning percentage in his career.

His last two losses have come at the hands of Nadal, although each of them went all three sets. In Madrid, Ferrer came within a tiebreak of upsetting the eventual winner.

If Ferrer can do a better job of getting his first serve in play, he will have a strong chance of getting a win at Roland Garros.

Stanislas Wawrinka

While Stanislas Wawrinka might be forced to miss the tournament due to a muscle tear, he can be a serious force if he is healthy enough to compete.

Wawrinka has a number of impressive performances this year, starting with a five-set loss to Djokovic at the Australian Open. Since then, he has continued to play well, especially on clay.

The No. 11 player in the world won a competitive tournament at Oeiras and then lost in the finals to Nadal at the Madrid Masters. In the latter event, he defeated quality opponents like Jo-Wilfried Tsonga and Tomas Berdych. 

He has been continually improving under coach Magnus Norman, and he has become a serious contender at Roland Garros.

Grigor Dimitrov

If there is one player who can derail Nadal's run at the French Open in an early round, it's Grigor Dimitrov.

For years, the Bulgarian has been known as "Baby Fed" due to his resemblance in play to Federer. He is great with his serve and is aggressive when given the chance.

However, he is now ready to become his own man. He defeated Djokovic in the second round of the Madrid Masters and continues to show that he is very tough to stop when he holds serve.

So far, he has struggled to take advantage of break opportunities but continues to get better at only 22 years old. If Nadal were to draw Dimitrov in an early round, he better be on his game right from the start.

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