French Open 2013: Outside Contenders Worth Watching at Roland Garros

While the Big Four of men's tennis have won every Grand Slam since the start of 2010, the sport's top players are by no means invincible. 

As Rafael Nadal's one and only loss at Roland Garros in 2009 proved, any player can win on any given day. In that spirit, it's time we take a closer look at some outside threats in the men's draw worthy of our attention. 

Here we'll showcase three men's contenders worth watching the rest of the way in Paris.

Nicolas Almagro (11)

An experienced clay-court player who has made deep runs at Roland Garros in the past, Spaniard Nicolas Almagro is always worth a look in Paris.

This year, the world No. 13 has already reached the third round of the men's draw, beating a pair of unseeded challengers in the opening rounds. In his most recent victory, a second-round win over Frenchman Edouard Roger-Vasselin, Almagro was able to win 78 percent of his first-serve points and an impressive 79 percent of his net points, converting on 11 of 14 chances at the net (via Roland Garros):

The 27-year-old has reached the quarterfinals three times at Roland Garros, most recently in 2012.

With Tomas Berdych having gone out in the first round, Almagro is in position to reach the quarters again and potentially earn his first-ever semifinal berth at a Grand Slam with fourth-seeded David Ferrer being the top player in his quarter of the bracket. 

Milos Raonic (14)

Big-serving Canadian Milos Raonic is off to a fast start at the French Open this summer after winning each of his first two matches in four sets. 

The 22-year-old took out Xavier Malisse in the opening round and then disposed of Frenchman Michael Llodra in Round 2, displaying tremendous poise in a pivotal third-set tiebreak.

Raonic's greatest asset was on display throughout the victory, as he served up 24 aces in the win. He would finish the match with five double faults but a ridiculous 75 winners in all (via Toronto Star Sports):

Although he is still learning and developing as a player, Raonic has made excellent strides in recent years and now finds himself in position to advance to the fourth round at Roland Garros for the first time in his career.

When he's serving well, Raonic is talented enough to win on any surface.

Gilles Simon (15)

French star Gilles Simon has been around much longer than Raonic but hasn't been able to achieve a high level of Grand Slam success over the course of his career.

Still, the 15th-seeded player in the men's draw is worth watching as he heads into the third round in Paris.

Down two sets to love in Round 1, the 28-year-old showed incredible heart to battle back, beating former Wimbledon and U.S. Open champion Lleyton Hewitt in five sets to advance to the second round at his home Slam. In the second round, Simon once again overcame a slow start to defeat Pablo Cuevas in four sets.

Simon was unstoppable over the final three sets, winning each by a score of 6-1.

Simon has reached the fourth round of the French Open just once in his career, back in 2011, but should be favored to get back there this summer before potentially matching up with second-seeded Roger Federer in a must-see Round-4 showdown.

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