With the 2013 U.S. Open in the books, it's time to look back on the elite players who left us unsatisfied.
While Rafael Nadal and Serena Williams were remarkably dominant in New York, each adding another major trophy to their impressive legacies, some other notable contenders came up surprisingly short, leaving them with plenty to prove the rest of the way.
Below, we'll examine three players with the most to prove following disappointing performances at the 2013 U.S. Open this summer.
After reaching the quarterfinals at 36 consecutive major tournaments, Roger Federer has now failed to reach the quarters at his past two Grand Slam events, falling in the round of 16 at the 2013 U.S. Open.
The shocking straight-sets loss to Tommy Robredo was his earliest exit from Flushing Meadows since 2003.
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Now, despite holding the No. 1 ranking just over a year ago after winning his seventh Wimbledon title, Fed is all the way down to No. 6 in the ATP world rankings, and he has a dozen losses already under his belt in 2013.
To put that number in perspective, Fed finished the year with 12 losses in each of the past two seasons.
But the most alarming fact by far is that Federer only has 35 match wins in 2013. That's less than half the amount he finished with in 2012, and it certainly adds fuel to the fire for those who talk about his impending decline.
After coming up short at the U.S. Open this year, 2013 marks the second year in the past three seasons Fed has gone 0-4 in majors.
Women's world No. 4 Agnieszka Radwanska has always struggled on the hard courts at Flushing Meadows. But after losing in the round of 16 for the second straight year, the 24-year-old Pole has something to prove.
Despite coming off a run to the semifinals at Wimbledon in July and some solid summer hard-court showings in Stanford, Calif. and Toronto, Radwanska reached the round of 16 at the 2013 U.S. Open only to lose to 24th-seeded Ekaterina Makarova in straight sets.
Even worse, the 25-year-old Makarova had never gotten past the third round at the U.S. Open prior to her upset win.
While Radwanska's best major performances have come on the grass at the All England Club, it must be noted that nine of her 12 career WTA singles titles have been won on hard surfaces.
Therefore, there's no excuse for her early exits at the season's final Slam.
One year after making a major breakthrough at the U.S. Open—reaching the semifinals in 2012 following a win over Roger Federer—Tomas Berdych failed to follow up with another strong run.
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Instead, the 27-year-old Czech bowed out in the round of 16, losing in four sets to the lower-seeded Stanislas Wawrinka after winning the opening set.
As the current world No. 5, Berdych has been knocking at the door of the Big Four for years but hasn't been able to win the big matches on the big stages. His latest failure at the 2013 U.S. Open only reaffirms that he's a step behind the giants of men's tennis.
Keep in mind that Berdych has yet to win a singles title in 2013. Considering he'll turn 28 this September, the 2010 Wimbledon finalist is running out of time prove he belongs among the best players of his generation.
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