Rafael Nadal of Spain hits a return during his men's singles tennis match against Nick Kyrgios of Australia at the Wimbledon Tennis Championships, in London July 1, 2014.
Rafael Nadal of Spain hits a return during his men's singles tennis match against Nick Kyrgios of Australia at the Wimbledon Tennis Championships, in London July 1, 2014. REUTERS

World's no. 2 Rafael Nadal will reportedly be sporting a vintage look in the forthcoming US Open series, bringing back the signature sleeveless shirt he used to wear from 2005 to 2009.

Nadal is now at the peak of his preparation for the upcoming North American hard-court season, where he's set to defend 4,000 ATP world ranking points along with the titles at the Rogers Cup, Cincinnati Masters and US Open championships.

According to Tennis Tonic, rumors have already started circulating since last week about Nadal wearing the sleeveless shirt - a vintage look for the Mallorcan Bull. Sportswear maker Nike hasn't confirmed the sleeveless foray, but Nadal was already spotted wearing the shirt during his training session in Mallorca.

"Rafael Nadal and Nike apparently decided to get back to 5 years and take out the famous sleeveless shirt from the closet. The rumor is all over the web even if Rafa and Nike haven't confirmed it, but Rafa has recently been spotted training in Mallorca with the famous sleeveless shirt... so probably the rumor is not misplaced," according to Tennis Tonic.

The 28-year old Nadal lost his grip of the top ranking in the ATP tour after failing to reach the quarterfinals of the Wimbledon Open. However, many fans and analysts still believed the reigning US Open winner will provide a strong fight to Novak Djokovic, Roger Federer and the rest of men's tennis in the coming weeks.

In a poll conducted by Tennis TV, Nadal blows away Djokovic as the big favorite, garnering 47 percent of the total votes. The Serbian ace is a far second with 23.6 percent of votes while Roger Federer (19.5 percent), Andy Murray (2.2 percent) and Grigor Dimitrov (2.2 percent) rounded out the top-5.

Toni Nadal, the uncle and coach of the 14-time Grand Slam winner, is aware that the upcoming battle on hard-court will be tougher for his nephew this year. He stressed that going 22-0 and winning the Rogers Cup, Cincinnati Masters and US Open will 'not be easy to repeat,' though he remains confident Rafa will still come on top in Flushing Meadows this year.

"It will not be easy to repeat those results" Toni said via Tennis Earth.

"But we will try. I am ready to sign straight away a paper if you tell me that Rafael will lose both the Masters 1000 and win the US Open."