By his own recent lofty standards the Australian had a rollercoaster round on Friday (Saturday AEST), even after making seven birdies and an eagle.
He was off to a nervous start when he made four birdies and three bogeys on the front nine, before solidifying with three birdies and an eagle as he stormed home.
It was unlike Thursday when he made nine birdies and an eagle in a bogey-free 61 that broke the course record.
"I feel like I made probably a similar amount of birdies to yesterday, I just couldn't get the momentum going by making bogeys thrown in there," Herbert said.
"It was not my best stuff out there, but that back nine kind of hung around long enough to see my chance to take the lead again come to fruition. So I just try to keep perspective on it. I still played decent."
Herbert's 66 was still the joint best round of the day and after his career-best major finish at the Open, where he tied for sixth, he has every right to believe another LIV win is on the cards following his triumph in Virginia in May.
His closest challenger is Bryson DeChambeau, whom he played with on Friday and will be paired with on Saturday after the American shot 67.
"It was great playing with Bryson today," Herbert said. "You kind of expect him to either hit a good shot or make every putt, and it kind of keeps you on your own game, just keeps you that little bit sharp on your own game, a little bit better."
DeChambeau appears to have overcome his theatrics at the Open where he was penalised two shots for a rules infringement and even threatened to give the weekend a miss as a result.
Speaking for the first time since the Open, DeChambeau admitted he could have contended for victory had it not been for the penalty and a poor performance on one hole.
"It was a good fight. I wish I would have given it more on Saturday and Sunday," he said.
"Felt like I could have. Besides the fifth hole and being three-over on that hole and then the 11th hole (triple bogey in the final round), that's six shots.
"That's tied for the lead right there. That's two holes and I'm right there with the Claret Jug."
But right now he has Herbert in his sights.
"I've got to focus on playing some really good golf, not making too many mistakes out there," said DeChambeau, who is second in the LIV season standings.
"Shoulda, coulda, woulda, right? We all know how that goes. It is what it is, four shots back and 36 holes of golf."
Australia's Cameron Smith (67) and Marc Leishman (68) are tied sixth at eight under.
Their good scoring gives Ripper a nine-stroke advantage over Crushers GC in the team competition, allowing the Australians to focus on their carrot-cutting competition away from the course.
England's Tyrrell Hatton (68) is in solo third at 10 under, and Byeong Hun An (68) of South Korea and Harold Varner III (69) are tied for fourth at nine under.
Season-standings leader Jon Rahm is effectively out of contention at one under in a tie for 31st.
with Agencies
