Needing a strong result in the third-of-four playoff events to crack the top 30 of the FedExCup standings and clinch a spot in the lucrative season-ending Tour Championship, Rose came out all guns blazing at the Cog Hill Golf and Country Club with birdies on his opening two holes.
Playing the back nine first, the Englishman would pick up his only bogey of the day at the 13th then played error-free golf the rest of the way, carding seven more birdies to equal the tournament’s opening round record for a two-stroke lead on Americans Mark Wilson and FedExCup leader Webb Simpson.
“I certainly probably didn’t expect that going out there today,” Rose told reporters. “Certainly my best round of the year by a long, long way, and could have been top five, top 10 rounds I’ve ever played for sure.”
Sitting just outside the top 30 when the day began, Rose will need to finish at or near the top of the leaderboard on Sunday to have a shot at the $10 million bonus that will go to the points leader after next week’s finale in Atlanta.
“I don’t know what I need to do,” said Rose. “I have the mindset I’ve got nothing to lose this week. That’s my strategy. That’s my attitude.
“Right now I’m not going to Atlanta. I’ve got everything to gain this week.”
Winner in two of his last three starts, Simpson brought his red-hot form to chilly Chicago with an unblemished six-under 65 while Wilson birdied the last hole to join the FedExCup leader at two back.
South Korean K.J. Choi carded a 67 to sit four off the pace, followed by American Jim Furyk, Australian John Senden and Colombian Camilo Villegas on three-under 68.
World No. 1 Luke Donald, who began the day fourth in the FedEx standings, got off to a horrendous start with bogeys on the opening two holes and never recovered following up with a double-bogey at the fifth before stringing together 13 straight pars for a four-over 75.
Phil Mickelson also stumbled out of the blocks with a double-bogey at the second and bogeys at four and five but he recovered in style with four straight birdies from the ninth to get back to level par before a bogey at 18 left him at nine shots off the pace.
In Saint-Nom-La-Breteche, France, Continental Europe picked up 3 1/2 out of five points in fourball matches Friday to reduce Britain and Ireland’s lead to one point in the Vivendi Seve Trophy.
Britain and Ireland led 4-1 after Thursday’s fourballs, but Continental Europe won three matches and halved one on Friday to cut the margin to 5 1/2 to 4 1/2 heading into the weekend.
Peter Hanson and Alexander Noren beat Englishmen Ian Poulter and Robert Rock 5 and 3 to give Continental Europe the first point.
Thomas Bjorn and Raphael Jacquelin halved their match with Simon Dyson and Jamie Donaldson.
Mark Foster and Lee Westwood defeated Anders Hansen and Francesco Molinari 5 and 3 for Britain and Ireland’s only win.
Miguel Angel Jimenez and Pablo Larrazabal beat Darren Clarke and David Horsey 3 and 2, while Nicolas Colsaerts and Matteo Manassero defeated Ross Fisher and Scott Jamieson by two holes.
Meantime, Finland's Joonas Granberg equalled the course record with 62 to lie a shot off the lead after the second round of the Macau Open on Friday, with Taiwan's Chan Yih-shin heading the field.
Chan, joint overnight leader at the Macau Golf and Country Club, recovered from an early bogey and saved a vital par with a 20-foot putt on the 15th on his way to a round of 67, to go nine under par for the tournament.
Asian Tour rookie Granberg recovered from his opening round 72 with pinpoint iron play, missing only one green and sinking an eagle at the 18th, and stands a good chance of adding to his win at the Selangor Masters in Malaysia in July.
Rikard Karlberg of Sweden, a two-time winner on the Asian Tour who had a share of the first round lead, also made eagle on the last hole for a 69 to sit in third place in the $750,000 event.
Starting on the back nine, Chan fired a superb eagle three on the second hole when his seven iron approach from 198 yards landed just nine feet from the pin, before adding two more birdies.
Jeev Milkha Singh of India, playing in his first Macau Open since 1999, got round in 68 to share fourth place with highly rated Thanyakon Khrongpha of Thailand and Australian Adam Groom, who carded 66 and 69 respectively.
