Who to Watch at the US Open 2014

— -- intro: The U.S. Open kicked off today in Flushing, Queens, in New York City. The world's best tennis stars will flock to Arthur Ashe stadium for two weeks of tournament play that lead up to a $1.5 million prize.

Here are the players to keep an eye on:

quicklist:1title: Roger Federertext: Roger Federer is the biggest name in the game, but the champion player is 33 and hasn't won a major championship in two years. His rival Rafael Nadal is sitting this one out due to a wrist injury, which means Novak Djokovic and Andy Murray are expected to be his biggest competition.media: 25118341

quicklist:2title:Novak Djokovic text: Djokovic likes the hard surface of the Open and has regularly beaten Federer and Nadal this year to land at Number 1 in the world, but he could face powerhouse Andy Murray in the quarterfinals. media: 25118047

quicklist:3title:Andy Murray text: England's Murray is coming off a back surgery that has left him struggling to advance to the finals in championships this year. He hasn't reached a final since he won Wimbledon in 2013.media: 25118824

quicklist:4title:Serena Williams text: Serena Williams is one of the older players in the field, at 32, but still a master of the game. She's won two consecutive U.S. Opens and could go for a third this year, but hasn't been playing well in 2014 so far. media: 25118561

quicklist:5title: Maria Sharapovatext: If Williams fails to advance in the Open it could leave room for Maria Sharapova, who has won five major championships but is often bested by Williams in direct competition. She previously won the 2006 U.S. Open.media: 25118626

quicklist:6title: Milos Raonic text: Milos Raonic has attracted attention after making it to the semifinals at Wimbledon before losing to Federer. He's a top talent but has not been able to beat Djokovic to take home the prize in two prior tournaments this year. media:

quicklist:7title: Grigor Dimitrov text: Dimitrov also made it to the semifinals at Wimbledon, has a track record of beating Raonic, and has beaten Andy Murray. He's also had trouble with Djokovic. media: 25118461

quicklist:8title: Eugenie Bouchardtext: Canadian newcomer Eugenie Bouchard has been in the semifinals of three Grand Slams this year and could be a match for Sharapova or Williams. The 20-year-old is currently ranked No. 8 in the world.

The Associated Press contributed to this report.

media: 25118691