The 2013 Shanghai Masters is in full swing as the world's top two men's players, Novak Djokovic and Rafael Nadal, announced their arrival with dominating opening-round wins on Wednesday.
Roger Federer also won his first match comfortably, inching one round closer to a potential quarterfinal tilt with defending tournament champion Djokovic. But while the three multiple-time Grand Slam champions might be the favorites to conquer the season's eighth Masters 1000 event, there are a handful of other threatening players lurking in China.
Below, we'll highlight a trio of dark-horse contenders capable of overthrowing the Big Three in Shanghai this fall.
Juan Martin del Potro (6)
2009 U.S. Open champion Juan Martin del Potro is in excellent form this fall and is coming off a title run in Tokyo last week.
He dropped the opening set against Philipp Kohlschreiber in his opening match in Shanghai, but ultimately over-powered his opponent, saving six of eight break-point chances and winning 71 percent of his total service points for the match.
The 6'6" Argentine with the blistering forehand will take on 11th-seeded Tommy Haas in the third round, but is 5-0 against the German veteran dating back to 2008.
Milos Raonic (10)
Like Delpo, big-serving Canadian Milos Raonic is playing tremendous tennis at the moment, having won 10 of his last 11 matches overall.
Raonic's impressive run includes a title in Bangkok last month, where he defeated the tournament's top two seeds, Richard Gasquet and Tomas Berdych to conquer Thailand. The 22-year-old is making aces look easy and leaves his opponents little hope, if any, when he's putting his first serves in the box.
Raonic has already earned victories over Michal Przysiezny and Fernando Verdasco in Shanghai. With a third win over eighth-seeded Stanislas Wawrinka on Thursday, he'll be staring down a potential showdown with Nadal in Friday's quarters.
Kei Nishikori (12)
Japan's Kei Nishikori hasn't been playing anywhere near the level of guys like Juan Martin del Potro or Milos Raonic coming into October, but the 12th-seeded contender is still a threat.
After all, he won the U.S. National Indoor Tennis Championships in Memphis earlier this year and won the Japan Open in 2012. All three of the 23-year-old's career singles titles have come on the hard courts, and its where he typically plays his best tennis.
Nishikori made short work of up-and-coming Bulgarian Grigor Dimitrov in Round 1 and overcame Jurgen Melzer in Round 2. And given Jo-Wilfried Tsonga's current form in the Far East, a victory over the top-ranked Frenchman in the third round will be far from impossible.
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