Chicago - Brandt Snedeker fired an eight-under 63 that included a sizzling stretch of seven straight birdies on Thursday to grab a one-shot lead after one round of the BMW Championship.
Snedeker defied gusty winds on the par-71 Conway Farms Golf Club course - hosting a PGA Tour event for the first time - and held a one-stroke lead over fellow American Zach Johnson.
Johnson, a two-time winner this year, had seven birdies in a flawless seven-under 64 and was two strokes in front of world number one Tiger Woods, former Masters champion Charl Schwartzel of South Africa, Steve Stricker and Kevin Streelman.
Reigning Masters champ Adam Scott, of Australia, posted a four-under 67, and shared seventh place with John Merrick, Ryan Moore and Nick Watney.
Snedeker opened on the back nine and his run of seven straight birdies began at 13.
"One of those days where everything seemed to go right in the middle of the round," Snedeker said.
The American came into the penultimate event in the US tour's FedEx Cup playoffs ranked ninth in the standings and already in line to become the first player to return to the Tour Championship the year after winning the playoffs crown and its $10 million bonus.
Sweden's Henrik Stenson, who shot to the top of the playoff standings with his win at the Deutsche Bank Championship two weeks ago, carded a one-over 72.
Woods, who came into the week at second in the playoff race, said his score could have been better but for a trio of missed putts from within five feet - two of them leading to bogeys.
"I'm not exactly real happy," said Woods, who had seven birdies to go with his two bogeys. "I played well and I just didn't get much out of that round."
Woods failed to birdie any of the three par-fives, although he finished on a good note with a long birdie putt at the par-four ninth, his final hole of the day.
"One of those days," Woods said.
Defending champion Rory McIlroy, who won this title last year at Crooked Stick, struggled to a seven-over 78 and was tied for 66th place.
His card included a triple-bogey seven at the par-four first hole - his 10th hole of the day - and a double-bogey five at the par-three 11th.
McIlroy, who came into the tournament at 41st in the playoff standings, needs a big turnaround to reach the top 30 and advance to the Tour Championship.
Leading first-round scores on Thursday in the $8 million BMW Championship, third event in the US PGA Tour playoffs (USA unless noted, par-71):
63 - Brandt Snedeker
64 - Zach Johnson
66 - Charl Schwartzel (RSA), Steve Stricker, Tiger Woods, Kevin Streelman
67 - John Merrick, Adam Scott (AUS), Ryan Moore, Nick Watney
68 - Roberto Castro, Gary Woodland, Hunter Mahan
69 - Nicholas Thompson, Rory Sabbatini (RSA), Kevin Stadler, Matt Jones (AUS)
700 - Brian Gay, Graeme McDowell (NIR), Harris English, Michael Thompson, Jason Kokrak, Chris Stroud, Sergio Garcia (ESP), Graham DeLaet (CAN), Phil Mickelson, Luke Donald (ENG), Bae Sang-Moon (KOR)
71 - Brendon de Jonge (ZIM), DA Points, Justin Rose (ENG), Jason Dufner, Bubba Watson, Charles Howell, Jordan Spieth, Jason Day (AUS), Angel Cabrera (ARG), Ernie Els (RSA)