Every tennis tournament has its group of favorites.  No matter how great the odds, however, favorites are not immune to upsets.  Roland Garros, with its slow red clay that has proven so conducive to creating momentum shifts, has seen its share of upsets throughout the decades.  There is little doubt that what transpires over the course of the 2015 edition of this prestigious event will only add to that list.

In the men's event, it is hard to envision anyone but a member of the Big Four raising the trophy.  But there are a handful of contenders outside the top 10 who could wreak havoc on the draw.

One man who is due for a good run in Paris is Grigor Dimitrov.  Although he struggled throughout the first quarter of this season, Dimitrov has started to get the ball rolling again on the clay.  He reached the quarters at both Monte Carlo and Madrid, as well as the semifinals of Istanbul.  He broke new ground last year by reaching the semifinals of Wimbledon, so he has experience going deep at a major.  And, in spite of the fact that he has never reached the second week of Roland Garros, given that his game is often compared with Roger Federer's, who has reached multiple Roland Garros finals, there is no reason Dimitrov cannot enjoy a similar amount of success on the dirt.

Another player who is showing himself capable of success on clay is John Isner.   He lost tight matches to Rafael Nadal in Monte Carlo and Tomas Berdych in Madrid before falling to the Spaniard again in Rome.  He has also enjoyed a good run this week in Nice, so he should arrive at Roland Garros with plenty of confidence.  With his towering stature, Isner is unlikely to be bothered by the way the ball can kick up the dirt, and he is still going to earn a decent number of free points on his serve.  Assuming he is able to keep the errors down, he is going to be a tough out for anyone.

A final man to consider at Roland Garros is the mercurial Fabio Fognini.  He has grown more consistent in his singles, and he has shown greater willingness to hang in the tough matches.  He possesses some surprising firepower and has the skills to play from anywhere on the court.  He has also done what many would not have thought possible in garnering two wins over Nadal on clay this year, so fans and the rest of the field know what he capable of.  Is he just as likely to go out in the first round as he is to make a deep run?  Sure.  But if he has come to play, no one should be taking him lightly.

Like the men's event, the women's tournament also features many players who could produce something unexpected, starting with Angelique Kerber.  While the German lost early in Madrid and Rome, but she went all the way to the title in Stuttgart, defeating Maria Sharapova and Caroline Wozniacki along the way.  Kerber is also a former top-five talent who has experience going deep at the majors, including reaching the second week of Roland Garros in the last three years.  She can be extremely consistent from the back of the court, but she is able to pull the trigger when necessary.  If she has mentally come prepared to fight to the last ball, she can get the job done against anyone.

In a similar boat to Kerber is Svetlana Kuznetsova.  Between her injuries and inconsistency, it is easy to forget that this Russian has won two majors, one of which was at Roland Garros six years ago.  After putting together a remarkable run to the finals of Madrid, however, she arrives in Paris with confidence.  Additionally, she has reached the second week of Roland Garros the last four years, so she knows how to get the job done on clay.  She also owns a solid all-around game.  If she proves able to play within herself, there is no reason that another trip to week two cannot be in the cards.  

At least one other woman worth consideration is Victoria Azarenka.  She played brilliantly against Serena Williams in Madrid, but it was evident she still was not quite ready to handle the big points after she squandered her opportunities to finish off the American.  She bounced back admirably in Rome, but her lack of consistency was once again on display in her one-sided loss to Sharapova.  Still, it was not all that long ago that Azarenka was the top-ranked woman in the world.  She has two majors under her belt and has reached the second week in Paris the last three years.  Clay may be her worst surface, but only a fool would completely discount her chances.

Will one of these players or another long shot outside of the top 10 emerge as a surprise at this year's Roland Garros?  Only time will tell.  But there is certainly enough talent on both sides to generate a Cinderella story or two, which should make for an exciting two weeks in Paris.