By John Reger
PACIFIC PALISADES, California (Reuters) - Dustin Johnson putted masterfully to card a bogey-free seven-under 64 and take a one-shot lead after the first round of the Northern Trust Open on Thursday.
Two-time defending champion Phil Mickelson shot a disappointing 72 to fall eight strokes behind Johnson.
Johnson, who started on the back nine, notched three birdies in his first five holes, featuring a monster 64-foot birdie putt on the 12th. He also converted birdie putts of 15 and 10 feet in his first nine.
The 25-year-old needed less work for his birdies on the back nine, holing putts from a foot, 6 feet and 14 feet.
More known for length in driving rather than accuracy on the greens, Johnson was ranked 62nd for total putts on the tour last year, and was 115th after two events this year.
Three players -- Alex Prugh, Rickie Fowler and Brett Lederer -- were unable to complete their round due to failing light and will return to the play their final hole of the first round on Friday.
(Editing by Ian Ransom; To query or comment on this story email email@example.com)