Charlie Wi seized a three-shot lead at the Pebble Beach National Pro-Am, following his tournament record nine-under 61 on Thursday with a three-under 69 in the second round.
The 40-year-old South Korean began the day tied for the lead with two others and he picked up in the second round right where he left off.
After his red-hot performance on the par-70 Monterey Peninsula course on Thursday, Wi played the par-72 Pebble Beach Links course on Friday.
He birdied two of his first six holes and had an eagle on the back nine to reach a 36-hole total of 12-under 130.
He was three strokes ahead of American Dustin Johnson, who shared the first-round lead in relation to par with Wi and Danny Lee of New Zealand. Johnson is alone in second after shooting an even-par 72 on Spyglass Hill.
Lee, Ireland’s Padraig Harrington, Vijay Singh of Fiji, Brian Gay and Brendon Todd were all tied for third at eight-under.
Johnson won back-to-back titles at Pebble Beach in 2009 and 2010, and is bidding to become the fifth player to have three or more victories at Pebble Beach.
Tiger Woods kept pace, but did not gain any real ground on the leaders with his two-under 68 on the Monterey Peninsula layout, considered the easiest of the three courses in the rotation.
Woods, who shot a 68 at Spyglass on Thursday, was tied for 17th, six strokes adrift of Wi.
Scores on Friday were not as low as the first round, which was played in sun-splashed, windless conditions. An unexpected heavy mist and cooler temperatures moved in quickly in the afternoon on Friday.
Singh played Spyglass on Friday, shooting his second straight 68 on the two more difficult courses, so he now has the luxury of playing Monterey in the third round.