Swiss Roger Federer should be among the freshest of the seeds as the Olympic silver medallist begins play at top men's seed at next week's ATP-WTA Cincinnati Masters.
The 17-time grand slam champion who turned 31 on August 8 only three days after losing to Andy Murray in the London Olympic final, took a few days off at his family chalet to recharge before hitting the practise courts in the USA last in the week.
The four-time champion won the Masters 1000 titles in 2005, 2007, and 2009-10 but suffered a quarter-final loss last year to Tomas Berdych.
Federer will start after a bye against the winner from Finn Jarkko Nieminen and Russian Alex Bogomolov.
The tournament has been plagued by injury pullouts, many a result of a jammed-up schedule made ever more demanding by the Olympics.
Among the men's absentees at combined event: Spaniard Rafael Nadal, Fernando Verdasco and Nicolas Almagro, along with the French pair of Gael Monfils and Olympic doubles silver medallist Jo-Wilfried Tsonga, who crashed into a Toronto fire hydrant this week and needed seven stitches in his knee.
Despite going nonstop since the Games where he exited without a medal, second seed Djokovic is carrying on for another week as the US open's August 27 start draws near.
Murray takes the third seeding despite the Scot having some doubt concerning his fitness after complaining of knee pain and pulling out after his first match in Toronto.
Murray is defending 1,000 ranking points as 2011 holder in Cincinnati. Spain's David Ferrer returns to post-Games action as fourth seed, ahead of Berdych, who will be trying to end a three-match loss streak dating to Wimbledon in June.
American Andy Roddick is back on tour and takes the 16th seeding as the 2003 and 2006 winner tries to rescue his 20th ranking on the eve of his 30th birthday.
The women's draw, headed by Poland's Agnieszka Radwanska with double 2012 Olympic champion Serena Williams on second, has suffered as well from the Games hangover.
Missing is Maria Sharapova, the silver medallist who has been suffering for a week with a stomach virus. She was joined as an absentee by WTA number one Victoria Azarenka, who withdrew from Montreal this week to rest a knee which she says has been troubling her.
Both will go into the Open with no hardcourt matches.
Czech Petra Kvitova is seeded fourth ahead of German Angelique Kerber.