4. Novak Djokovic
After an elbow injury kept Novak Djokovic sidelined for the most part of 2017, his resurgence in 2018 has been phenomenal. Djokovic's coach Marian Vajda and fitness expert Gebhard Gritsch deserve a lot of credit too for his 4th Wimbledon title.
The Serb has had a good run-up to the the US Open this year. He has been silently pushing himself up the ATP rankings, having reached the quarterfinal of the French Open, the final of Queen's club and then winning the Championships at Wimbledon.
Having already claimed the crown at Flushing Meadows in 2011 and 2015, the Serb would definitely be one of the favorites going into the year's final Grand Slam. We shouldn't be surprised if we see Djokovic playing in front of the Flushing Meadows crowd on 9th September, fighting for the title.
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