LOS ANGELES, February 14, 2014 (AFP) - Johnson teed off early, and while his five-under effort had him just one stroke in front of a big chasing pack, no one managed to join him atop the leaderboard before darkness halted play with 15 players on the course.
They included JB Holmes, who was among four players who briefly grabbed a share of the lead only to fall back.
After a birdie at 13 -- his sixth of the day -- Holmes bogeyed 16 to fall into the chasing group and was in trouble at 17 when play was suspended.
In all, 10 players were in the clubhouse on four-under par 67, including South Korea's Bae Sang-Moon, Italian Francesco Molinari, Australian Matt Jones and US tour sensation Jimmy Walker.
Walker, whose triumph at Pebble Beach on Sunday was his third of the 2013-14 season, birdied his last three holes to reach four-under.
In all, 10 players were in the clubhouse on four-under par 67, including South Korea's Bae Sang-Moon, Italian Francesco Molinari, Australian Matt Jones and US tour sensation Jimmy Walker.
Walker, whose triumph at Pebble Beach on Sunday was his third of the 2013-14 season, birdied his last three holes to reach four-under.
Johnson's six birdies on the par-71 Riviera Country Club Course, which played firm and fast in the warm California sunshine, included three in a row at 17, 18 and one.
After his only bogey of the day at the par-three fourth he bounced back with a birdie at his penultimate hole, the eighth, to separate himself at the top and set a target for the afternoon starters.
"I just got off to a good start and just continued to play really solid all day," said Johnson, who was happy to be back at the classic course in the canyons west of downtown Los Angeles.
"I kept it in play, and hit a lot of greens, had a lot of looks at birdie."
Johnson opened the 2013-14 US PGA Tour season with a victory in the World Golf Championships HSBC Champions in Shanghai back in November.
He finished equal sixth at the Tournament of Champions in January, and on Sunday grabbed a share of second place behind Walker in Pebble Beach with a final-round 66.
Johnson hit all but two greens in regulation and needed just 30 putts.
"The game's right where I want it to be," Johnson said. "Any score under par out here is a pretty solid round. It's a tough course, but it's right in front of you, so it's just a golf course that I really like."
While Johnson enjoys the challenge of Riviera, Garrigus said he had to convince himself of the course's charms.
"I just stopped telling myself that I hated this place," said Garrigus, whose best finish in four prior starts here was a tie for 51st.
"I convinced myself this is my favorite golf course of the year and I tell you what, this is the best shape I've ever seen it."
Walker was also full of praise for Riviera, and enjoying the added buzz from the fans in the wake of his Pebble Beach win.
"I can feel it," he said of the extra energy around his group.
"I can hear it. It's different. It's really fun to have everybody watch last seek and say 'good job' and 'way to win' and 'keep it going.'
"It's fun," Walker added.
Leading first-round scores on Thursday in the $6.7 million US PGA Tour Northern Trust Open (round halted by darkness, to resume Friday. USA unless noted, par-71):
66 - Dustin Johnson
67 - Robert Garrigus, Francesco Molinari (ITA), Scott Stallings, Charley Hoffman, Matt Jones (AUS), Brian Harman, Blake Adams, Jimmy Walker, Bae Sang-Moon (KOR), Charlie Beljan
68 - Jim Furyk, Cameron Tringale, Brendan Steele, Keegan Bradley, Rickie Fowler
69 - William McGirt, Richard H. Lee, Kevin Stadler, Charl Schwartzel (RSA), KJ Choi (KOR), Lee Westwood (ENG), Harold Varner, James Driscoll, Matt Every, Jason Kokrak, Ryan Moore, Angel Cabrera (ARG), Marc Leishman (AUS), George McNeill