All eyes have been on the top seeds at the 2013 U.S. Open in Flushing Meadows this summer, and as a result, there are several threatening contenders flying under the radar early on.
Whether they're coming off of impressive runs a year ago, hitting their stride at the right moment or simply playing too well to ignore, these players are in the mix and their strong starts make them worth watching as the tournament continues.
Below we'll highlight three dark-horse singles contenders who are sure to build off their fast starts in New York.
Milos Raonic (10)
Big-serving Canadian Milos Raonic made short work of Italy's Thomas Fabbiano in Round 1, winning in straight sets after surviving a dramatic second-set tiebreak.
Raonic's serve was on point in the comfortable victory. The 22-year-old finished the match with a ridiculous 28 aces to zero for Fabbiano. Raonic won 86 percent of his first-serve points and 74 percent of his service points in all.
The men's No. 10 seed will take on unseeded Spaniard Pablo Andujar in the second round.
Raonic reached the fourth round in Flushing Meadows a year ago and will be favored to get back in 2013, considering he wouldn't face a player seeded higher than him until the fourth round, where No. 8 seed Richard Gasquet could potentially be waiting for him.
Ana Ivanovic (13)
Serbia's Ana Ivanovic reached the quarterfinals at the U.S. Open in 2012, marking the best finish of her career at the season's final Slam. In 2013, the 25-year-old is already off to a scorching-hot start.
Ivanovic blasted first-round opponent Anna Tatishvili, defeating her in straight sets in a match that lasted less than an hour. The victory was highlighted by some dominant return play from the women's No. 13 seed.
The 2008 French Open champion won 32-of-49 receiving points for the match and broke Tatishvili seven times overall.
Having reached the quarters in Queens a year ago, Ivanovic has the confidence to make a deep run. The fact that she's playing lights-out tennis to start the tournament is just a bonus.
Maria Kirilenko (14)
Three-time Grand Slam quarterfinalist Maria Kirilenko is off and running at the U.S. Open after steamrolling Yanina Wickmayer in the first round of the women's draw.
Kirilenko only dropped two games in the straight-sets victory, converting on 5-of-11 break-point opportunities to wrap up the match in just under an hour. Although the competition will get stiffer as the 26-year-old Russian makes her way through the draw, she'll have a great shot to reach her first Grand Slam semifinal.
The reason: Kirilenko landed in Sara Errani's quarter of the draw. The clay-court specialist and world No. 5 has struggled on the hard courts this summer and has been past the third round in New York just once in her career.
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