Prospects: Whenever a tournament starts, the smart money inevitably tends to gravitate towards Djokovic. Yet he is not infallible as Sam Querrey showed in the last 32 of Wimbledon before Del Potro did likewise in the opening round of the Olympics.

The Serb starts as a solid favourite to defend the title he won against Roger Federer a year ago, but history suggests he is slightly vulnerable in New York. He won the Rogers Cup on a hard court in Toronto last month, and it will be interesting to see if he can rediscover his stride having appeared to be unbeatable in the first six months of the year.

Novak Djokovic of Serbia holds up the US Open trophy after defeating Roger Federer of Switzerland

Image credit: Reuters

This is the first Grand Slam in 2016 where Djokovic has not looked a certainty. The field are closing in, and much will depend upon Djokovic's mental mood.

Prediction: Semi-finals

Andy Murray (Great Britain)

Age: 29

World ranking: 2

Grand Slam wins: 3

Wimbledon 2013, 2016
US Open 2012

2016 titles: 4

Rio de Janeiro Olympic Games (Outdoor/Hard)
Wimbledon (Outdoor/Grass)
London / Queen's Club (Outdoor/Grass)
ATP World Tour Masters 1000 Rome (Outdoor/Clay)

Odds: 2/1

Prospects: He might not be the favourite, but he is highly fancied. After losing in four sets to Djokovic in the French Open final, Murray has embarked upon a long hot summer that has included victory at Queen’s, Wimbledon and the Olympic Games in reeling off 22 straight matches. He lost to Marin Cilic in the final of Cincinnati, but that was more down to fatigue than a loss of form.

Back with Ivan Lendl, the coach who cajoled him into winning his first US Open four years ago, Murray himself has admitted he is playing the best tennis of his life. If Djokovic is not up to his normal excellence, Murray can capitalise to win back-to-back Grand Slams.

Andy Murray kisses the US Open trophy after his triumph in 2012 (Reuters)

Image credit: Reuters

Prediction: Champion

Milos Raonic (Canada)

Age: 25

World ranking: 6

Grand Slam wins: 0

2016 titles: 1

Brisbane (Outdoor/Hard)

Odds: 14/1

Prospects: Always the bridesmaid, never the bride? Raonic is struggling to shake off his nearly man tag after nearly making the Australian final in January before losing to Andy Murray in five sets and nearly winning Wimbledon before falling short against Murray in three sets.

If there is one man Raonic will hope to avoid in New York it is Murray, who also returned from Rio to overturn him in straight sets in last week’s Cincinnati semi-final. In terms of the Grand Slams, this season has been the most productive of Raonic’s career and he should be expected to go further than his best so far in New York, which surprisingly has only been the last 16 in 2012, 2013 and 2014.

Milos Raonic beat Roger Federer to reach the Wimbledon final

Image credit: AFP

Can he win it? His serve is big enough, but it could all depend upon how kind the draw is to him.

Prediction: Quarter-finals

Juan Martin del Potro (Argentina)

Age: 27

World ranking: 142

Grand Slam wins: 1

US Open 2009

2016 titles: 0

Odds: 14/1

Prospects: Delpo’s rebirth was arguably the feel-good story of the Olympic tennis in Rio. Not only is Del Potro a great champion, he is also a good guy. He was ranked as high as four in the world at the outset of the 2014, and his surge to the final of the Olympics - that included wins over Djokovic and Rafael Nadal - suggests Del Potro is getting back to optimum level after a torrid period fighting surgery to an ongoing left wrist problem over the past two years that almost buried his career

He lost to Murray in four sets on a sluggish surface in the Rio final, but the faster courts of Flushing Meadows should enhance his prospects. Has been handed a wild card for the US Open, and he is more than just a dangerous floater with a forehand that will make Arthur Ashe Stadium shudder.

Juan Martin Del Potro in Rio

Image credit: AFP

It may be too much to expect to lift the trophy, but he should be viewed among the serious candidates to enjoy a run. Djokovic, and others, will be praying he does not come across the Argentine in New York.

Prediction: Final

Marin Cilic (Croatia)

Age: 27

World ranking: 9

Grand Slam wins: 1

US Open 2014

2016 titles: 1

World Tour Masters Cincinnati

Odds: 25/1

Prospects: Is finding some serious form at the right time of the season. He downed Murray in two sets in the Cincinnati final, and the surface at Flushing Meadows is made for an on-form Cilic as he showed by thumping Roger Federer and Kei Nishikori to win his only Grand Slam two years ago.

Seems to have been about a fair bit longer than his 27 years, but is a really dangerous customer who should expect to go deep into the tournament. If his weapons of big serves and booming forehand are working, he could win this for a second time.