Tough openers for the top seeds

Djokovic, who has been bothered by a wrist injury, faces towering Jerzy Janowicz of Poland in his opening match at Flushing Meadows, and is likely to meet 48th-ranked Jiri Vesely of the Czech Republic in the second round.

Vesely beat the Serbian world number one earlier this season on clay in Monte Carlo.

"I'm doing everything in my power ... to make sure that I'm as close to 100 percent as possible," said Djokovic, who hurt his wrist in Rio a few days before the start of the Olympics, where he lost in the first round.

Williams, recovering from a shoulder injury that contributed to her third-round exit in Rio, drew Russian lefthander Ekaterina Makarova as her first opponent.

The 34-year-old American, seeking to break her tie with Steffi Graf for most grand slam singles titles in the Open era on 22, has a 4-1 career record against Makarova, but lost to the Russian in the fourth round at the 2012 Australian Open.

Williams is in a strong quarter that also includes fifth seed Simona Halep of Romania and 16th-seeded Australian Sam Stosur, who beat the American in the 2011 US Open final.

Djokovic is seeded to face either Frenchman Richard Gasquet or big-serving American John Isner in the fourth round, with France's Jo-Wilfried Tsonga or 2014 champion Marin Cilic, who ended Andy Murray's win streak in the Cincinnati final, as possible quarter-final opponents.

Men's second seed Murray, who ran off 22 wins in a row including his second Wimbledon title and successful defence of his Olympics crown, appeared to get a more favorable draw.

He faces Czech Lukas Rosol first, has Grigor Dimitrov of Bulgaria or Feliciano Lopez of Spain as potential fourth-round foes with Japan's sixth-seeded Kei Nishikori possibly waiting for him in the quarters.