FedEx Cup leader Dustin Johnson is in a three-way tie at the top of the Tour Championship leaderboard after an opening round of 66.
The American propelled himself to the top of the FedEx Cup standings with victory at the BMW Championship last time out and made a strong start on Thursday, as he looks to claim the $10million bonus on offer to the overall winner of the play-off event.
The world No.2 carded a birdie at the last to join Hideki Matsuyama and Kevin Chappell as overnight leaders on four-under, one stroke ahead of world No.1 Jason Day, American Kevin Kisner and Si Woo Kim of Korea.
Johnson will guarantee the FedEx Cup title with victory at the Tour Championship but a top-five finish could also be enough.
The in-form 32-year-old insists he is not feeling the pressure despite the $10million up for grabs.
“I know there’s a lot on the line, but there’s a lot on the line every week,” said Johnson. “I come out with the same mentality. I felt really relaxed out there all day.”
Rory McIlroy, the only member of Europe’s Ryder Cup team to qualify for the Tour Championship, recovered from two double bogeys on the front nine to keep himself in contention with a two-under 68.
McIlroy can still win the FedEx Cup but must win the Tour Championship and hope Johnson finishes second or lower.
Defending FedEx Cup champion Jordan Spieth is also on two-under alongside England’s Paul Casey and Justin Thomas.