Collin Morikawa watches his shot on the 11th hole Friday during the second round of the U.S. Open at The Country Club in Brookline, Mass. Morikawa shot a 66 to grab a share of the lead at 5 under, tied with Joel Dahmen. Robert F. Bukaty/Associated Press

BROOKLINE, Mass. — The storms dodged Brookline and the stars began to emerge Friday in the U.S. Open.

Collin Morikawa showed signs of emerging from pedestrian play at just the right time, matching the low score of the championship with a 4-under 66 for a share of the 36-hole lead with Joel Dahmen and a shot at a third straight year winning a major.

He had plenty of company near the top of the leaderboard at The Country Club, including one player in clear view.

Defending champion Jon Rahm played with Morikawa and did his best to keep pace with an eagle and a series of big par putts that felt just as valuable. Rahm had a 67 and was one shot behind in a group that included Rory McIlroy.

McIlroy, coming off a win at the Canadian Open, was never more entertaining.

He was two holes into his round when an errant approach landed in waist-high fescue. He took a hack. And then another. The third try finally found the green, and he holed a 25-foot putt to salvage a double bogey. McIlroy hit his stride on the back nine with three birdies over his last four holes for a 69.

Scottie Scheffler shot 67 in the second round Friday and was two shots out of the lead in the U.S. Open at The Country Club in Brookline, Mass. Charlie Riedel/Associated Press

Not to be overlooked was Masters champion Scottie Scheffler, who chipped in from thick rough short of the par-5 14th green for an eagle that brought the Texan back into the mix with a 67. He was two shots behind.

“It’s the U.S. Open. No one has taken it deep so far and kind of run away,” Morikawa said. “The last few days is a huge confidence booster for me heading into this weekend, and hopefully we can kind of make some separation somehow.”

Morikawa, Rahm and Scheffler have combined to win four of the last nine majors. And then there’s McIlroy, who has four majors by himself, but none since 2014.

“I think it’s great for the game of golf that the highest ranked players and the best players are up there, especially in the tournament where truly the best player ends up winning,” Rahm said.

Caleb Manuel, a 20-year-old amateur from Topsham, improved by nine strokes in his second round, shooting a 74 for a two-day total of 17-over 157.

The idea of the U.S. Open is to identify the best players. Some of them require some introductions to major championship contention on the weekend.

Start with Dahmen, the cancer survivor and everyman who will never be accused of taking himself too seriously, even if he takes his game seriously. He thought about withdrawing from the 36-hole qualifier twice last week, before it started and after the first round.

But he stuck it out, and with a 68 on Friday, plays in the final group of a major for the first time. He joined Morikawa at 5-under 135.

The group one shot behind includes Hayden Buckley, who actually studied while at Missouri because he never thought playing golf for a living was going to work out. He wasn’t in the U.S. Open until making a 20-foot birdie putt in a playoff for the last spot in his qualifier 11 days ago.

He was fading, like so many others, with three bogeys during a five-hole stretch around the turn, when he got back on track. Birdies on the last two holes gave him another 68.

Also at 136 were Aaron Wise, with one PGA Tour victory and nothing better than a tie for 17th in his nine previous majors; and Beau Hossler, who finished tied for 29th in the U.S. Open at Olympic Club as a teenage amateur in 2012 but hasn’t been heard of since then in the majors..

They were examples that the U.S. Open being open to all doesn’t just stop with qualifying for the right to play the toughest test in golf.

The weekend won’t include Phil Mickelson, hardly a surprise. He took a four-month hiatus over his inflammatory remarks about the PGA Tour and the Saudi-backed league he was promoting, wound up joining LIV Golf and returned to competition last week with poor results.

The U.S. Open was a slightly stronger test and Mickelson was exposed, particularly on the greens, with rounds of 78-73 to miss the cut. His next stop is Oregon in two weeks for another LIV Golf event, 54 holes and no cut.

Signs posted warned of the potential for bad weather as the wind started to shake trees late in the morning. The clouds dispersed and the wind died late in the afternoon, allowing for better scores and a few less mistakes.

McIlroy never panicked after his double bogey. He took advantage of the birdie chances on the drivable par-4 fifth and the short par-5 eighth. And he finished strong to get right in the mix, his main goal going into the weekend.

Adding to the anticipation for McIlroy was seeing so many familiar names at the top.

“You want to go up against the best to try to bring the best out of yourself,” McIlroy said. “And to see Collin and Jon and Scottie and Sam (Burns) up there and whoever else, that’s what major championship golf is all about. That’s what competition is all about.

“And that’s at the heart of this game. I’m excited to be in that mix going into the weekend.”