HAVEN, WIS. – Midway through the first round of the PGA Championship, there was an interesting procession near the 18th fairway.

An all-terrain vehicle rushed past, on a narrow footpath outside the ropes, almost tipping over when its righthanded tires hit a berm. A woman in the back of the vehicle was crying, and holding her bandaged left shoulder.

A worried relative hurried after, slipping and almost falling himself. Then came an elderly woman displaying a fan's version of course knowledge.

She cruised by, wielding large ski poles.

Whistling Straits can be a difficult course if you hit the ball errantly, or if the wind asserts itself, or if you'd simply like to walk near the course without falling down. Thursday morning, the craggy, pitted course, still damp from early-week rains, played like a muni for quality ball strikers, and Dustin Johnson might be the bell cow of that category.

Johnson took advantage of calm conditions to shoot a 66 and take the first-round lead. Because the terrain did not bother him, the weekday warrior has again positioned himself to deal with the bunkers, hazards and prevailing winds between his ears.

In 2010, Johnson led going into the final day of the U.S. Open and shot an 82. He lost a chance to make a playoff at the PGA that year when he infamously grounded his club in what the tournament had ruled to be a bunker, costing him two strokes.

This year, he blew the U.S. Open and shot a 75 under easy conditions on Sunday at the British Open to blow another chance.

Thursday, he took a one-shot lead over the field. Because of where he is and who he is, the round felt less like an accomplishment than a warning.

Asked about his confidence given his strong play and epic collapses, Johnson said, "I don't know. Your guess is as good as mine."

Johnson has held the lead or a share of it in five of the 13 major rounds this year. In four first rounds of majors this year, he is 20 under. He is the first player in the modern era of golf to shoot a 66 or better in the opening round of a major three times in a single season.

His scores by rounds this year in majors: First: 22 under. Second: 15 under. Third: 3 over. Final: 3 over.

Johnson might be the best athlete on tour. He might be the best all-around ball striker. He might be the worst on tour at dealing with pressure.

Thursday, he laid up at the par-5 second hole, squandering his power. He laid up for the same reason some people do morning yoga. "I wanted to make today as easy as possible," he said.

He made birdie at the second, and at the intimidating par-4 fourth, where he hit his drive 336 yards, then hit a wedge to about 8 feet. Johnson cruised around with five birdies, an eagle and only one bogey.

"I would prefer to be in the lead," Johnson said. "There's less shots you've got to make up."

His philosophy is borrowed from Yogi Berra, his final-round tenacity from Greg Norman, golf's patron saint of blown leads.

"I want the lead, for sure," Johnson said. "All I'm looking for is a chance to get it done on the back nine on Sunday."

Wednesday, Johnson said he was "chillin'," which might have been a first at a major tournament. Thursday, he noted that his approach seemed to work. "Today was pretty easy, I would have to say," he said.

Given the changing conditions, the round of the day was produced by David Lingmerth. The Swede shot a 67 and was one of only two players who played in the afternoon to finish the round in the top 15.

Lingmerth won the Memorial in June. At the British Open, he shot a 29 on his first nine holes, but a 40 on the back nine and a 77 on Sunday.

Johnson and Lingmerth made golf look easy Thursday, meaning they will both probably be around to revisit how hard the game can be on a major championship Sunday.

Jim Souhan's podcast can be heard at MalePatternPodcasts.com. On

Twitter: @SouhanStrib. • jsouhan@startribune.com