Paul Casey could do no wrong as he shot a career-low eight-under 62 to take the lead by four shots after the third round of the Travelers Championship.
The Englishman moved into 16 under for the tournament, surging clear of the pack, with Russell Henley back at 12 under in outright second.
Casey showed just how in form he was with an eagle on the par-four 15th.
He hit an amazing 18 out of 18 greens on Saturday, just a couple of days after he was not pleased at all with his swing.
"We worked on it hard yesterday afternoon after the round," Casey told CBS Sports.
"Pretty simple, posture wasn't good enough and I was standing too far from the golf ball... and literally he [swing coach Peter Kostis] had me on the range, had me feeling like I was going to shank everything yesterday and I played comfortable."
Henley is in second after a three-under 67.
World number nine Jason Day shot one of the best rounds of the day with a four-under 66 and the Australian sits in a tie for sixth at 10 under.
"It's been a pretty good week with the short game," Day said after finishing his round with a mere 26 putts.
"Out of the bunkers, there's really good sand here, but also just around the greens in general, just been chipping really nice."
Rory McIlroy had a lot of trouble on the greens as he finished with a three-putt to end his day with a one-under 69. He is eight under for the tournament.
World number two Justin Thomas shot an even-par 70 and sits at five under.
James Hahn (67) provided one of the highlights of the round with a hole-in-one at the 11th.