As the US Open betting season slowly approaches, a lot of bettors start to take more and more notice of what is happening in the Masters Series events prior to the big event. All eyes have been on Rafael Nadal and for good reason. Everyone knows that the Roger Federer express is on track to win another US Open – this would be his sixth consecutive one, for those who are counting – and the only guy that can derail that train is Nadal.

Nadal has been battling knee problems for the first time in his career this year and a lot of people aren’t sure whether this will be a regular thing from this point on or whether this is just one rough season. Nadal is the type of player that goes all out and plays with reckless abandon, so it’s not surprising that his body is breaking down, but it is surprising that his body is breaking down at the age of 23.

The betting public got their first look of Nadal when he came back from a month-long absence at the Rogers Cup in Montreal. Previously, Nadal had been surprisingly upset at the French Open, when he was among everyone’s sports picks to win the event, and then was forced to pull out of Wimbledon with his knee injury.

At the Rogers Cup in Montreal, Nadal struggled and was upset far earlier than anyone expected. He’s fared a little better at the Masters Series in Cincinnati, which to some is a good sign. After struggling to beat Andrea Seppi, needing tie-breakers in both sets to win, Nadal finally looked like himself against No. 31 seed Paul-Henri Mathieu with an easier win.

The issue was that after the match, Nadal still mention that he is suffering from knee tendinitis, which figures to be an ongoing issue. The hard court surface is the least forgiving on the knees, which means Nadal simply isn’t going to be 100% when it comes to the US Open.

Roger Federer is on a role right now. He’s surpassed Pete Sampras’ record for Grand Slams, he’s finally got that elusive French Open Championship, and now the pressure is off of him to just go out and play great tennis.

Over the last five years, Nadal has been the only player on the Tour to consistently beat Federer and if he’s not healthy, don’t expect anyone else to be able to. Those who sports bet online should stick with Federer as their pick at the US Open.