Rory McIlroy's chances of securing a payday of 11.5 million US dollars suffered an early double blow in the Tour Championship in Atlanta.
With only the top five at East Lake in full control of their own destiny, sixth-placed McIlroy knew he had to win the final event of the PGA Tour season and see other results go his way to claim the overall FedEx Cup title and USD10million bonus.
However, after recovering from three-putting the first hole with three birdies in succession from the third, the four-time major winner then double-bogeyed the seventh and eighth to fall down the leaderboard.
McIlroy, who is the only member of Europe's Ryder Cup team competing in the 30-man event, hit a poor chip to the seventh and compounded the mistake with another three-putt, before finding water with his approach to the next.
A two-over-par front nine of 37 left the 27-year-old six shots off the lead being shared by Kevin Kisner and Kevin Chappell, but also five behind FedEx Cup leader Dustin Johnson. Even if Johnson were to finish second outright, it would be enough to end McIlroy's FedEx Cup chances.
US Open champion Johnson, who won the BMW Championship a fortnight ago, had birdied three of his first six holes as nearest rival and playing partner Patrick Reed recovered from two early bogeys to get back to level par.
Johnson and Reed were among eight members of the United States Ryder Cup team in the field, with captain Davis Love naming his final wild card after the tournament finishes on Sunday evening.
World number seven Bubba Watson, Justin Thomas and Daniel Berger are the favourites to be selected, but Berger failed to make a good first impression after struggling to an opening four-over-par 74.
Two-time Masters champion Watson fared slightly better with a 72 after dropping shots on the 16th and 17th, with Thomas one over after 13 holes.
England's Paul Casey, who began the week fifth in the standings, reached two under par after birdies on the fourth and fifth, but drove into the water on the eighth to run up a double bogey and dropped another shot on the 10th.
McIlroy's rollercoaster round continued on the back nine as the world number three carded a second hat-trick of birdies from the 12th to get back into red figures for the day.
At one under par he was also within three of the lead shared by Johnson, Chappell and Hideki Matsuyama, with Johnson picking up his fourth birdie of the day from just two feet on the 12th.
Matsuyama had birdied the 18th to complete his 66, but Chappell had to settle for the same score after three-putting the last from 30 feet for a disappointing par.