Dustin Johnson’s first-round 66 is pretty great

Dustin Johnson is no stranger to the sacred sports grounds of Southern California. It was about three weeks ago that he took the field at Dodger Stadium, in front of a sellout crowd.

Johnson is engaged to Paulina Gretzky, daughter of the Great One. So, when the Kings and Ducks played at the ballpark, Johnson and the rest of the family watched the teams warm up on the makeshift rink behind the pitcher’s mound, posed for a group photo, and saw Wayne Gretzky drop the ceremonial first puck.

“It was cool just to be a part of it,” Johnson said.

By the time this weekend is up, center stage could be all his. Johnson shot a five-under-par 66 Thursday at Riviera Country Club, emerging as the leader after the first round of the Northern Trust Open.

The group of 10 golfers to shoot a 67 includes Jimmy Walker, who won two of his previous three PGA Tour events, and Charlie Beljan, who lost last year’s Northern Trust Open in a playoff. The defending champion, John Merrick, shot a one-over 72.

Of the 144 entrants, 15 did not finish the first round because of darkness. That includes J.B. Holmes, who was four under through 16 holes. Those players will complete their round Friday, then proceed directly to the second round as scheduled.

Merrick won last year at the 10th hole — the second playoff hole — when he made par and Beljan missed a five-foot putt.

“That did not end the way I wanted it to,” Beljan said. “Today I made a par on No. 10, and I was very pleased with that.”

Walker birdied the last three holes to close within one shot of the lead. He won at Pebble Beach last week, joining Tiger Woods, Phil Mickelson and David Duval as the only players to win three times in his first eight events of the season.

He said he was so excited he awoke at 4 a.m. Monday and Tuesday — “completely fired up and ready to go,” he said — and did a national morning show interview at 4:30 a.m. Wednesday. Fans who would not have known him a year ago now follow him along the course and offer congratulations; the media is all over him.

Walker, 35, turned pro in 2001. He has three career victories, and he says he enjoys the sudden rush of attention.

“I don’t know what it’s like for some of these guys that have won 40 times,” he said.

Johnson, 29, has won eight times in his career. He has had the first-round lead five times, winning three of those events.

He shot a 64 for the first-round lead here in 2010, but a third-round 74 doomed his chance of winning. He finished tied for third that year, tied for fourth here in 2012.

“I’ve just really liked this golf course,” he said. “It’s a great, great golf course.”

That is not a universal opinion among the players. Robert Garrigus, among the 10 players tied at 67, had played nine rounds in this tournament. His best score at Riviera had been 69; his average 73.

Garrigus did not play a practice round to adjust his game. He said he decided to adjust his attitude instead.

“I just stopped telling myself that I hated this place,” Garrigus said. “I convinced myself this is my favorite golf course.”

Johnson is plenty fine with the course, and with his game. He finished second to Walker last week, and he has shot 66 in each of his past two rounds — Sunday in the cold, wind and rain at Pebble Beach, and Thursday in the warmth and sunshine at Riviera.

Johnson played in the morning Thursday, then left with enough confidence to spend the afternoon relaxing, rather than frantically checking scores every five minutes to see if his lead would hold up.

“I won’t look,” he said. “It doesn’t matter. It’s the first day. I’m just worried about me.”

bill.shaikin@latimes.com

Twitter: @BillShaikin