Rafael Nadal has just started his fourth stay as the world No. 1 in men's singles tennis ranking. With AndyMurray deciding to skip Cincinnati Masters, and Roger Federer's further withdrawal, the Spaniard had no emotions at all. His fourth reign at the summit has just begun, but there are numerous questions to be answered to. The North American preparation for US Open Tennis Championships had Nadal in a position to cement his status, especially in Cincinnati. Losin in the quarterfinals to the eventual runner-up Nick Kyrgios, he missed the chance to put some distance between him and Federer.

Dealing with a minor injury, the 36-year-old Swiss is expected to start his own bid for the world No. 1 spot at Flushing Meadows in New York. For Nadal, the outdoor summer swing is below expectation so far, so the US Open may be the right place to make an impact.

Rafael Nadal seeks a third US Open title

15 times Grand Slam champion, Nadal prevailed twice in New York (2010 and 2013). Overall, he reached the final act on three different occasions losing the 2011 edition to Novak Djokovic. But, the past years lacked luster on this event with Nadal struggling to reach the higher stages. Since his last success (2013) he never got past the fourth round, so despite being the new world No. 1, he may not be a clear favorite.

On the other side, if he'll go all the way he could use those ranking points to keep a safe distance between him and his rival Roger Federer. Besides, with Federer and Nadal sharing the Grand Slam pot this season, that surreal race of the most successful Grand Slam history is on the table once more. If Nadal wins in New York, he will be just three clicks behind Federer.

But, if Federer prevails, he will go up to 20 putting a strong five distance in between.

Nadal is not at his peak

Suffering two unexpected losses Nadal lost some rhythm. First, he came short against Denis Shapovalov at Rogers Cup in Montreal as the 18-year-old Canadian delivered one of the biggest shocks of the current season.

Then, with No. 1 spot already in his pocket, Nadal went on losing to Nick Kyrgios at Western & Southern Open in Cincinnati. The second defeat wasn't that surprising as Kyrgios is known for his appetite to slay giants.

In 2017, as usual, Nadal had his peak of form during the clay court season back in the spring. Winning three titles in a row (Monte Carlo, Barcelona, and Madrid) gave him the leverage to go all the way at Roland Garros where he came out triumphant for the tenth time. Since then, his tennis output has been less sharp and damaging. He would love a complete run at US Open as it would give his fourth reign a fresh, shining look.