AKRON, August 2, 2014 (AFP) - The Spaniard was a sedate one-under for the day through nine after a birdie at the second hole. But he caught fire after the turn at Firestone Country Club.
A birdie at 10 was followed by a par at 11, before Garcia raced home with birdies at the last seven holes to match the course record and build a 36-hole total of 11-under 129.
He was three strokes ahead of England's Justin Rose, who posted a three-under 67 for 132.
"I've been fortunate to have some good rounds, but I think that was my lowest round in tournament play and also my lowest nine holes. So, it was very nice," Garcia said.
"I did get a little bit lucky on the front nine. I hit three bad tee shots and I got good breaks, and was able to save par. And that kept my round going."
Recently crowned British Open champion Rory McIlroy fired a six-under 64 for 133, where he was joined in third place by overnight leader Marc Leishman of Australia, who posted a one-under 69.
Rickie Fowler, who shared second at the British Open with Garcia, fired a 67 to share fifth place with South African Charl Schwartzel (69) on six-under.
Garcia, who tied for second behind McIlroy in the Open at Hoylake in July, moved to the top of the leaderboard when he rolled in a 12-foot birdie putt at 16.
With his closing two birdies, he matched the course record of 61 set by compatriot Jose Maria Olazabal in 1990 and twice matched by Tiger Woods, in 2000 and 2013.
Woods carded a 61 in the second round here last year on the way to his eighth triumph at Firestone.
On Friday the 14-time major champion had to settle for a one-over 71 that left him one-under for the tournament and tied for 25th.
The 38-year-old superstar is playing just his third event since back surgery on March 31.
He needs strong finishes this week and in next week's PGA Championship at Valhalla if he is to make the US PGA Tour's FedEx Cup play-offs and give himself more tournaments to impress US Ryder Cup captain Tom Watson.
Woods said his play on Friday wasn't going to get the job done.
"I didn't hit the ball well. I didn't putt well. I didn't do anything well," Woods said after posting three birdies and four bogeys.
"The only thing I did well was I fought hard, grinded hard. Unfortunately, it wasn't very good today."
- Garcia 'thrilled' -
For Garcia, it was a fantastic day.
He closed his round with 11 consecutive one-putts and along the way set a Firestone back-nine record of eight-under 27.
Garcia landed his third shot at the par-five second two feet from the cup and made that for birdie.
After seven straight pars, he drained a 20-footer at the 10th.
After a par on 11, Garcia stuffed his tee shot inside a foot at 12.
He followed with a three-foot birdie putt at 13. He drained an 18-footer for birdie on 14, then holed another birdie at 15.
After taking the lead with his birdie at 16, he poured in a 25-foot birdie putt at 17 and drained a 20-footer at the last.
"I started to hit the ball very good on the back nine," Garcia said. "I rolled the ball nicely, so I'm thrilled with it."
Rose teed off on 10 and rebounded from a bogey at 14 with a five-foot birdie at 15.
He made a short birdie putt at 18, then rolled in a 12-footer for birdie at the first. Rose notched another birdie on the fifth before closing with four pars in a row.
"That was a stark contrast to my round yesterday. Yesterday, I scrambled it around and made everything. Today, I hit it much closer to the hole, gave myself plenty of looks, but didn't quite make as many," he said.
Leading second-round scores on Friday in the $9 million World Golf Championships-Bridgestone Invitational (USA unless noted, par 70):
129 - Sergio Garcia (ESP) 68-61
132 - Justin Rose (ENG) 65-67
133 - Marc Leishman (AUS) 64-69, Rory McIlroy (NIR) 69-64
134 - Rickie Fowler 67-67, Charl Schwartzel (RSA) 65-69
135 - Patrick Reed 67-68, Keegan Bradley 68-67
136 - Graham DeLaet (CAN) 67-69, Brandt Snedeker 68-68, Hunter Mahan 71-65
137 - Jim Furyk 69-68, Adam Scott (AUS) 69-68, Thomas Bjorn (DEN) 69-68, Henrik Stenson (SWE) 71-66, Francesco Molinari (ITA) 67-70, Matt Kuchar 71-66
138 - Gary Woodland 70-68, J.B. Holmes 69-69, Harris English 69-69, Ryan Moore 65-73, Noh Seung-Yul (KOR) 69-69, Jamie Donaldson (WAL) 68-70, Miguel Angel Jimenez (ESP) 69 69
139 - Bubba Watson 69-70, Tiger Woods 68-71, Jimmy Walker 69-70
140 - Steven Bowditch (AUS) 69-71, Ernie Els (RSA) 71-69, Zach Johnson 70-70, Bill Haas, 71-69, John Senden (AUS) 74-66, Branden Grace (RSA) 69-71, David Howell (ENG) 69-71, Matt Jones (AUS) 70-70