Wimbledon champion Andy Murray won't be able to defend his U.S. Open title after falling in the 2013 quarterfinals to Stanislas Wawrinka.
Murray fell 6-4, 6-3, 6-2 in what was an incredibly disappointing performance. Now, rather than facing the winner of Novak Djokovic and Mikhail Youzhny in the semifinals, Murray will be forced to watch the others play on.
Despite the disappointing loss, it should still go down as a successful Grand Slam season for the Scottish sensation, who reached the final of the Australian Open and conquered the All England Club. Yet, winning the season's final major would have made a huge statement.
The top four isn't as defined as in past years. Aside from Novak Djokovic, who has assumed top-dog status, there's change at the top. Murray and a revitalized Rafael Nadal have been battling for the No. 2 spot while Roger Federer has begun to slide.
Winning two straight majors and defending his title in New York would have established Murray as a serious threat to Djokovic's top spot in the coming months. Now, he faces a much tougher uphill battle to reach No. 1 for the first time.
Although the mainstream spotlight tends to leave tennis after the majors end, there are still several key tournaments on the horizon. The Shanghai Masters, BNP Paribas Masters and ATP World Tour Finals are among the big events left to contest.
Winning the U.S. Open obviously would have given Murray some momentum heading into that final stretch.
Still, it's an important upcoming schedule for Murray. Starting with the London Olympics, he's been on a quite a roll on the biggest stages of the sport, but he hasn't always been able to match those results at the smaller tournaments, which is essential to reaching the No. 1 ranking.
The bright side coming out of the U.S. Open loss is that Djokovic has a lot of points to defend in the remaining tournaments. So a hot streak for Murray over the next few months, most notably at the Masters events and the Tour finals, should allow him to make some progress.
Chasing the No. 1 ranking is the main challenge for Murray, and Federer's slide out of the top five heading into the season's final major helps, as well as Fed's early exit. It takes away one of the players who stood in his way for the past couple seasons.
Yet, Djokovic's continued dominance and Nadal's strong play recently means reaching the mountaintop won't be easy.
Murray has made notable progress, but in an era where there's been so many other elite players battling at the top, it takes a sustained run of terrific play to reach No. 1. A strong finish to the 2013 season would be a major step in that journey for the Wimbledon champ.
Being unable to defend his U.S. Open title will be a disappointment, but Murray must regroup quickly and finish the year on a high note.