Roger Federer on Upset Alert Against Jo-Wilfried Tsonga at 2013 French Open

Roger Federer is one of the greatest tennis players to ever live, but he's in danger of being ousted in the quarterfinals of the 2013 French Open by hometown hero Jo-Wilfried Tsonga.

Federer barely escaped Round 4 against Gilles Simon, winning the arduous five-set match 6-1, 4-6, 2-6, 6-2, 6-3. He had the match well in hand until an unfortunate tumble in the second set caused him to lose momentum, as noted by Roland Garros' official Twitter account:

Simon quickly seized upon Federer's poor luck and rallied to win the second set. He then dominated the third set as Federer labored, but in the end, Federer's will was too strong and he overcame his mid-match stagnation.

The crowd at centre court went wild cheering for both players throughout the match and rose as one to celebrate the brilliant match, as noted by the official Twitter account of the Shanghai Rolex Masters:

After Federer's match against Simon, he spoke with reporters about his tumble, via Julien Pretot of Reuters:

"

I didn't hurt myself or anything. But maybe I did lose that touch of confidence for a little bit, and then I was out of the match there for a bit. But I think more credit to him, because I wasn't bothered by the fall in any way, actually. If anything, [it was] mentally, or maybe it gave him a mental boost. Who knows what it was.

"

Fans of Federer are certainly breathing a sigh of relief knowing that he's not injured, but the fact remains that Simon—a player who isn't nearly as much of a threat as Tsonga—was able to take him to the limit.

Meanwhile, over on a lesser court, Tsonga swiftly and easily defeated his fourth-round opponent, Viktor Troicki, in straight sets. The Frenchman hasn't lost a single set through four rounds, and he's going to be as fresh as a spring rain for his match against Federer in the quarterfinals.

Over the course of their careers, Federer has gotten the better of Tsonga, winning nine of their 12 total matches. That said, Tsonga took Federer to five sets in the quarterfinals at the Australian Open this year and defeated him in the quarterfinals a couple of years ago at Wimbledon. 

He's a big, strong player who moves well for his size. He loves to utilize his heavy serve to get his opponents off-balance for his returning volley, and after reaching the quarterfinals last year at Roland Garros, he'll certainly have a full contingency of support from his home crowd. 

Should these two players meet 10 times, chances are Federer will win seven out of those 10 matches. He's a superior overall player who isn't fazed by any type of adversity—as he impressively demonstrated on Sunday with his fourth-round comeback—and his experience will serve him well against Tsonga in the quarterfinals. 

That said, should Federer fail to show up at his absolute best, Tsonga is ready to take full advantage of any shortcomings. Should Federer take a tumble in the quarterfinals, Tsonga will win.

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