Rory McIlroy enjoyed a positive start to the Tour Championship in Atlanta as he completed day one at the top end of the leaderboard.
McIlroy carded an opening round of four-under-par to finish the day tied for third and three shots behind leader Henrik Stenson.
The former world number one – who was usurped by Jason Day last week – carded a bogey at the Par 3 second hole but responded with consecutive birdies at seven, eight and nine.
McIlroy added another birdie at 11 before dropping a shot at the next.
But he finished the round strongly with birdies at 14 and 17 to finish on four-under.
Australian Day surprisingly stumbled after beginning his reign as world number one in brilliant fashion in pursuit of a fifth win in his last seven events in the Tour Championship.
Day overtook McIlroy at the top of the rankings after winning the BMW Championship on Sunday, his second victory in three FedEx Cup play-off tournaments and fifth of the year.
The 27-year-old was 101 under par for his last seven events, including a major championship record of 20 under in winning the US PGA Championship at Whistling Straits.
And he looked to have carried on exactly where he left off yesterday, carding birdies on the first three holes at East Lake before slicing his drive on the fifth out of bounds to run up a triple-bogey seven.
He would go on to finish the day on one-under-par.
Day is top of the FedEx Cup standings and, along with Jordan Spieth, Rickie Fowler, Stenson and Bubba Watson, would secure the overall title and USD10million bonus with victory on Sunday.
Stenson could even claim the eight-figure payday for the second time in three years without winning all season, but the Ryder Cup star had also birdied the first three holes before picking up another shot on the sixth.
He eagled the ninth and fird birdies in at 10 and 12, before finally dropping a shot at the 17th.
England’s Paul Casey had set the early clubhouse target after six birdies and one bogey in a 65.
Casey, who has not played in the Tour Championship since 2010 after suffering from injuries and a loss of form, told Sky Sports 4: “It’s great to be back. I have been through a lot since then so it’s wonderful to be among the top 30 with a chance of winning the FedEx Cup.
“It’s a course I really like, very classic. It sets up very well for my game; you have to put yourself in good position off the tee, a high ball flight helps and these greens are as quick as Augusta.”
McIlroy admitted that the bonus money “luckily, doesn’t sort of mean much to me anymore” but insisted he was determined to add the FedEx Cup title to his CV after finishing second 12 months ago.