Rafael Nadal's Biggest Key vs. Martin Klizan at 2013 French Open

Rafael Nadal may be a heavy favorite heading into his second-round match against unseeded Martin Klizan on Friday at the 2013 French Open, but he'll be vulnerable to an upset if he doesn't continue to exercise patience.

Patience will be Rafa's best friend on Court Suzanne Lenglen on Day 6 as he looks to advance to the third round of the men's draw for the ninth straight time.

A 23-year-old Slovakian, Klizan plays left-handed just as Nadal and stands 6'3", which is about all that the world No. 35 has going for him in this match as he looks to pull off the shocker. 

In his first-round victory over Daniel Brands on Monday, Nadal stumbled out of the gate, dropping the first set 6-4 before nearly losing the second in a dramatic tiebreak. Had it not been for an unforced error by Brands in that tiebreak, Nadal may have had to navigate his way back from two sets down. 

But instead, the three-time reigning champion's patience prevailed in a key moment, as Brands missed a crucial volley, re-energizing Rafa and sending him on his way to a four-set win.

Having won more titles at Roland Garros (seven) than anyone else in the Open era, Nadal is well aware that players will be gunning for him, throwing everything they have at him and hoping for the best. His ability to remain patient and focused on his approach is what will potentially propel him to an eighth title in Paris this summer. 

His forehand and movement are key of course, but both have become muscle memory (via Roland Garros):

Patience is something Nadal must remind himself of over the course of a match, whether it's immediately after making a critical unforced error or following a brilliant winner struck by an opponent. 

Without it, his mistakes and his opponent's winners can impact more than just the scoreboard.

Despite being the favorite, Rafa has always played as if he was the underdog, playing all out but never overreacting to mistakes or phenomenal plays. 

No one is doubting whether Nadal has the physical tools to win a fourth consecutive French Open championship and his eighth in nine years, but the question is: Can Rafa hold up mentally and continue to win with a monumental target on his back?

To do so requires loads of patience, something that Nadal must exercise against the upset-minded Martin Klizan in Round 2.

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