Novak Djokovic is a major doubt for the US Open which commences on 28 August due to a bruised bone suffered from excessive playing.

The world number four was hoping to win Wimbledon for a fourth time earlier this month following his second title of the year in Eastbourne.

Read more Mats Wilander reveals the change Roger Federer made to compete with Rafael Nadal and Novak Djokovic

However, he was forced to retire during his quarter-final match at SW19 against Tomas Berdych due to an elbow injury, having already trailed 7-6, 2-0.

With the elbow injury troubling the Serbian ace for 18 months, seemingly being the cause of his poor performances in the calendar year, it was suggested that he take a long break to recover.

According to Zdenko Milinkovic, a Serbian doctor who Djokovic had consulted, the former world number one may have to rest for six to 12 weeks, which would likely rule him out for the final Grand Slam of the year in New York.

"Symptoms have calmed down, he was with a specialist in Toronto for additional tests," Milinkovic was quoted as saying on Sportski Zurnal via the Sydney Morning Herald. "He also consulted our experts. Now it's important to look at the different types of procedures that can affect recovery."

"He has a bruised bone due to excessive playing. Novak clenched his teeth and continued playing despite a serious injury. It was always a big concern for me as his friend."

The Serbian newspaper also states Djokovic will "99 percent" miss the US Open which he won in 2011 and 2015 as well as Serbia's Davis Cup semi-final against France in September.

While Djokovic will end a run of 51 consecutive Grand Slam events, the need for a long break might have come at the right time with him and his wife Jelena expecting a second child in the next few weeks.