Dustin Johnson leads at Riviera as Mickelson struggles to a 72

Phil Mickelson rubbed his eyes and shrugged. He waved his arms right and left, trying to encourage his golf shots to follow his direction to the proper spots on the fairways and greens.

Not enough of them did.

Mickelson, the second-ranked golfer in the world who on Wednesday had proclaimed himself pleased with the state of his game, shot a humble 72, one over par, in the first round of the Northern Trust Open at Riviera Country Club on Thursday.

He is the two-time defending champion, trying to become the first to win the event three times in a row. But Mickelson bogeyed four of his last seven holes and is tied for 83rd, eight shots behind leader Dustin Johnson.

Johnson, 25 and the winner of last year’s rain-shortened AT&T Classic at Pebble Beach, recorded seven birdies and no bogeys in his seven-under 64. That was good for a one-shot lead over Andres Romero of Argentina and Kevin Stadler, the 2002 Pacific 10 Conference player of the year from USC and son of 1982 Masters winner Craig Stadler.

The 6-foot-4 Johnson is a long-hitting, down-home Southerner (from Myrtle Beach, S.C.) with a bit of a troubled past, somewhat reminiscent of Arkansas-raised, big-hitting but troubled John Daly.

Johnson was arrested on suspicion of drunk driving last March and in 2001 he was one of five teenagers who took part in a burglary where a gun was stolen. He pleaded guilty to a charge of second-degree burglary but was eventually pardoned.

On Thursday, playing with major champions Angel Cabrera and Justin Leonard, Johnson started early on the back nine and sneaked in with his sparkling round about the time Mickelson teed off.

Johnson is already a two-time winner on tour and he birdied two of his first three holes Thursday. He was particularly pleased with the 50-foot putt he sank on the par-four 12th hole.

“After that,” he said, “I had good vibes going all day.”

Johnson also expressed an appreciation for the historic old course.

“It really fits my eye well,” he said. “It’s a fun course to play. You’ve got to hit every club in your bag.”

Stadler too knows this course well. He played it while he was at USC, and his father won here in 1996. And he is well aware that two weeks ago, Bill Haas won the Bob Hope Classic, a tournament his father, Jay, had won. They were the eighth father-son team to post PGA Tour wins. Should Stadler win this, he and his dad would join that group.

“It was cool to see Bill win,” said Stadler, who also suggested it was less inspiring to be told how much he resembles his portly father. “Unfortunately, yes, I do see the resemblance. Pretty much everybody else does too.”

Mickelson, meanwhile, had none of the constant attention that has followed him since he made his controversial decision at last week’s Farmers Insurance Open to use the Ping Eye 2 wedge, an old club with square grooves. All such clubs have been ruled “nonconforming” as of Jan. 1, but because of a lawsuit settlement, the Ping is still allowed.

The growing dispute prompted Mickelson on Wednesday to ditch the Ping for now.

On Thursday, Scott McCarron, who started it all by saying use of the club was cheating, shot a 74 here.

And at the end of the day, Mickelson’s red-rimmed eyes looked tired and he answered only three questions.

“I was three under and had a decent round going,” he said. “Another birdie here or there and I’m right in it and I ended up with four bogeys coming in. It really wasn’t a good round.”

diane.pucin@latimes.com