(Reuters) - The return to form and fitness of a host of big names in the men's draw at the U.S. Open has strengthened the field for the year's final Grand Slam but Rafa Nadal, Novak Djokovic and Roger Federer are still the favourites for the title.
The trio have dominated the highest level of the sport for years and Djokovic's victory at Wimbledon, combined with an impressive hard court season, sees him edge defending champion Nadal as the bookmakers' pick to succeed at Flushing Meadows.
The sixth-seeded Serb has played his way back to form after a shaky start to the year following his return from a long-standing elbow injury that needed surgery, and is on the opposite side of the draw to top seed Nadal.
Second seed Federer, now 37, is on the same side of the draw as 31-year-old Djokovic and they could meet in the last eight at Flushing Meadows.
Nadal stormed to victory last year in a field weakened by the absence of several top 10 players, but to win a fourth U.S. Open title he will have to outlast seven former champions.
The Spaniard, fresh from victory at the Rogers Cup, where won his 33rd Masters 1000 title, has been coy about his chances in New York given how well his main rivals have been playing, but is counting on the atmosphere to give him a lift.
"The energy here in New York is difficult to compare with another place. I love the night sessions, I love the connection with the crowd. I feel very comfortable always here," the 32-year-old Nadal said in a recent interview.
Behind the three favourites, the return of 2016 champion Stan Wawrinka, given a wild card by the organisers after making a comeback from a knee injury, and Andy Murray, returning after hip surgery, adds another layer of stiff competition.
Croat Marin Cilic and Argentine Juan Martin del Potro complete the ranks of former winners who will attempt to reclaim the title, while Alexander Zverev's decision to hire Ivan Lendl as his coach also offers up an intriguing prospect.
Zverev is arguably the strongest of the next generation of players who have long been tipped to break the big three's hold on the sport's biggest prizes.
At 21, the German is ranked fourth in the world but his temperament is suspect and Lendl, who coached Murray during the most productive spell of the Scot's career, might help his young charge finally fulfill his potential.
"I think (Zverev) gets down on himself. He gets emotional and I think it does affect his play," 18-times Grand Slam winner Chris Evert, who will be part of ESPN's coverage of the U.S. Open in New York, said on a conference call.
"I think if it's true that Lendl is coaching him now -- what he did with Andy Murray was phenomenal -- if he can improve the mental and emotional.. side of his game, I think Zverev will have it all."
(Reporting by Simon Jennings; Editing by Ken Ferris)