Andy Murray heads into the US Open at Flushing Meadows as the man in form after a summer of glory which has seen the Scot claim back-to-back triumphs at Wimbledon and the Olympic Games in Rio de Janeiro.
However, with Roger Federer absent and both Rafael Nadal and Novak Djokovic’s form uncertain, it is one of the first major tournaments in recent years when attention has not immediately focused upon what had been mens’ tennis’ established top four.
Sport360 takes a look at the men to watch in New York.
Novak Djokovic (SRB)
ATP ranking: 1
Grand Slam singles titles: 12
US Open best: Won in 2011 and 2015
The Serbian is the top seed but has some serious injury issues. Djokovic underwent electric shock-style treatment to heal his wrist injury, but is still not 100 per cent fit.
What could make his title defence at Flushing Meadows harder is his admission that his private life has been in turmoil.
But if he is even remotely fit, Djokovic will be a big threat.
Andy Murray (GBR)
ATP ranking: 2
Grand Slam singles titles: 3
US Open best: Won in 2012
With Novak Djokovic unfit and Roger Federer not playing, the spotlight will be on Murray, who will look to add to his 2012 title.
The Wimbledon and Olympic champion has another motivating factor – he can finish the year ahead of Djokovic as the world No 1.
While that mark is some time away, Murray knows there is a lot at stake.
Stan Wawrinka (SUI)
ATP ranking: 3
Grand Slam singles titles: 2
US Open best: Semi-finals in 2013 and 2015
The two-time semi-finalist arrives in New York in indifferent form, having split his last 10 matches.
Wawrinka had to withdraw from the Rio Olympics due to injury but is now back in business.
However, Wawrinka has delivered good results at the US Open, making it to the quarter-finals or beyond in his last three appearances at Flushing Meadows.
Juan Martin del Potro (ARG)
ATP ranking: 141
Grand Slam singles titles: 1
US Open best: Won in 2009
A brilliant Rio Olympics campaign earned del Potro a US Open wild card.
At the Games, the Argentine stunned Novak Djokovic and Rafael Nadal before losing to Andy Murray in the final.
If he stays injury free, can be a big threat.
Marin Cilic (CRO)
ATP ranking: 9
Grand Slam singles titles: 1
US Open best: Won in 2014
The Croat ended Andy Murray’s 22-match winning streak to win the Cincinnati Masters and moved back into the top 10.
Don’t be surprised if he mounts a serious challenge in his attempt to add to his 2014 US Open title.
Grigor Dimitrov (BUL)
ATP ranking: 24
Grand Slam singles titles: None
US Open best: Fourth round in 2014
Dimitrov has brought a sense of discipline to his game. In Cincinnati, was classy yet efficient as he made it to the semi-finals.
The work put in by Dani Vallverdu, former member of Andy Murray’s coaching staff, is working.