Roger Federer: Breaking Down the Swiss Star's Biggest Threats at the US Open

With the men's side of the bracket set to begin play at Flushing Meadows for the 2012 U.S. Open tournament on Sunday, all eyes will be fixated on world No. 1 Roger Federer.

The Swiss star comes into the Open fresh off a win at the Western & Southern Open in Cincinnati and is hoping to take home his first Grand Slam in the U.S. since 2008.

Despite his hot hand, it hasn't all been easy for Federer in this 2012 ATP tour season. 

He struggled right out of the gate, causing speculation that the 31-year-old's brilliant reign was over. But, as always is the case with Federer, he came back strong in the second half of the year and regained his top dog spot after claiming a seventh Wimbledon championship.

With Rafael Nadal out of the tournament this year with an ailing knee, the field feels a lot less stacked than in previous years.

Regardless, there are still some major threats to Federer taking home the 2012 U.S. Open. Here's a breakdown of the biggest threats to the world's best tennis player.

Andy Murray

The last time Federer and Murray played on a big stage, Murray got the Wimbledon monkey off his back, defeating the world's top-ranked golfer in straight sets to capture the gold medal at the 2012 Summer Games.

But Murray's return to the hard court after the Olympics has gone anything but smooth. The Scottish star had to withdraw from the Rogers Cup with a knee injury after the second round and got upset in Cincinnati in the third round by Jeremy Chardy, giving Murray just five matches of competitive tennis since London.

For the 25-year-old to atone for his semifinals loss to Federer at Flushing Meadows in 2011, he'll have to get the rust off in his early round matchups.

If he avoids an upset, Murray could finally have the confidence to take down his Swiss rival when the two meet on their side of the bracket. 

Novak Djokovic

With Nadal absent for this Slam, the tennis world fully expects to see a U.S. Open final between Federer and Djokovic.

The 25-year-old Serbian took down Nadal in the 2011 final and comes in as the 3/2 favorite (via Bovada.lv) to repeat as champion.

Considering it's been four years since Federer took home the crown at Flushing Meadows, it's not hard to see why.

But to get to the final that so many think are inevitable, Djokovic will need to avoid major upsets and re-establish himself as the dominant force he was a year ago.

Andy Roddick

It's been nine years since a 20-year-old Andy Roddick came away with his first and only major championship at Flushing Meadows.

But no matter how much the 29-year-old American is struggling, Roddick seemingly gets up for the Open every year and 2012 should be no different.

The former world No. 1-ranked player thrives on the energetic crowd and comes up big every year with his whole country rooting him on.

With Nadal, the player who knocked him out last year, out of the picture, the only man that stands in the way of a Federer-Roddick finale is Djokovic. Taking down the Serbian machine is obviously no easy task, but we've seen amazing things from Roddick at Flushing Meadows in the past.

There's absolutely no reason to count him out this year.