BETHESDA, Md. (AP) — In one of those can't-miss moments in sports, thousands of fans covered every inch of space on the hill behind the 10th green at Congressional. They spilled onto the clubhouse veranda, pressed their faces against the windows and lined up against the balcony railing to watch Rory McIlroy deliver a performance never before seen in the U.S. Open.

"It was Tiger Woods of 11 years ago," Ian Poulter said.

In some respects, it was even better.

McIlroy, the sympathetic figure at the Masters, was as close to perfect as golf allows Friday during a stunning assault on the record book. The 22-year-old from Northern Ireland became the first player in the 111-year history of the U.S. Open to reach 13-under par, and despite a double bogey into the water on the final hole, his 5-under 66 was enough set the 36-hole scoring record at 131.

He had a six-shot lead over former PGA champion Y.E. Yang (69), matching the U.S. Open record set by Woods in 2000 at Pebble Beach for the largest margin at the halfway point.

McIlroy went 17 holes without missing a green. He went 35 holes without making a bogey.

"It's very near the best I can play," he said.

Not since Woods destroyed his competition at Pebble Beach in 2000 for a record 15-shot victory has anyone made golf look this easy, at least for two rounds.

As if playing under complete control were not enough, McIlroy hit a wedge from 114 yards some 15 feet behind the flag on No. 8, then watched it roll down a slope and into the cup for eagle. The only time he came close to making bogey was on the par-4 11th, when he blasted out of a bunker to 8 feet and made the putt.

He tied the U.S. Open record of 12 under — previously held by Woods in 2000 and Gil Morgan in 1992, both at Pebble Beach — on the par-5 16th with a 4-iron from 223 yards that settled 8 feet from the cup.

"I told him, 'I don't think you'll see a better golf shot,'" his caddie, J.P. Fitzgerald, said.

Then came the 17th, when McIlroy hit 7-iron from 175 yards that covered the flag, barely cleared the bunker and left him 15 feet below the hole for yet another birdie to go to 13 under.

That number just isn't seen on leaderboards at the U.S. Open.

"It's crazy, isn't it?" Steve Stricker. "Pretty incredible what he's done so far."

McIlroy knows better than to start the celebration before Sunday. He was buoyed by support coming into the U.S. Open because of the calamity at Augusta National from two months ago, when he led by four shots going into the final round of the Masters and shot 80, the kind of collapse that isn't easily forgotten.

"It's been two very, very good days of golf," McIlroy said. "I put myself in a great position going into the weekend. But I know more than probably anyone else what can happen. So I've got to stay really focused and try and finish this thing off."

The second round was halted for 42 minutes because of thunderstorms, and Yang held it together on the stronger back nine to at least stay in range. The South Korean is no stranger to big deficits in the majors. It was only two years ago, in the 2009 PGA Championship at Hazeltine, that he trailed Woods by six shots going into the weekend and wound up winning by three.

"I'm not going to chase anyone," Yang said. "I'm just going to play my game."

Sergio Garcia had a 71 and joined Snedeker at 2-under 140 among those who finished the second round. Just his luck — and Garcia doesn't have much of that in the majors — he is playing solid golf at a major where someone else is playing out of this world.

Also at 140 were Matt Kuchar, Robert Garrigus and former Masters champion Zach Johnson.

"It's only two days," Johnson said. "I'm not going to give it to him yet."

The second round was suspended by darkness, forcing 21 players to return Saturday morning to complete their round. And it left everyone who finished wondering if there was any chance of catching McIlroy.

"Rory is obviously running away with it, so we are pretty much playing for second unless something crazy happens tomorrow," PGA champion Martin Kaymer said. "I hope he wins, though. He's a nice person and he deserves it, especially after the Masters."

Lee Westwood wasn't ready to concede after a 68 left him 12 shots behind, although he made yet another reference to Pebble Beach in 2000 when he said his goal was second place, and added, "We'll see what Rory does."

"He's had leads before," Westwood said.

As for what advice he would give McIlroy?

"I'm supposed to beat him over the next two days," Westwood said. "I'm hardly going to give him advice, am I?"

It was hard to ignore what felt like a coronation for McIlroy as he eased his way around the golf course. Toward the end of his round, the gallery in the grandstand gave him a standing ovation as the freckle-faced wonder boy with the bounce in his step simply walked onto the green.

McIlroy played with four-time major winner Phil Mickelson, one of the biggest crowd-pleasers in golf who simply was along for the ride. Mickelson, who also made double bogey on the 18th, shot a 69 to finish at 1-over 143.

"He's striking it flawlessly and putted great on the greens," Mickelson said. "His first two rounds were very impressive."

During one stretch on the front nine, Mickelson made three birdies in four holes and didn't make up any ground. McIlroy laid up from the rough on the par-5 sixth and hit wedge to 5 feet for birdie, then holed out for his eagle on the eighth.

The burst of cheers when the ball dropped for eagle was enough to make the group ahead take notice as they stood on the ninth tee. There was Retief Goosen, hands on hips, looking over at the green. Stricker took one last look as he walked off the tee to confirm his suspicions on who hit the shot.

Deep down, he knew it all along.

"We figured it was probably him just the way he was going," Stricker said.

McIlroy wasn't finished. From 190 yards, he hit a 6-iron to about 5 feet behind the hole at No. 14 for birdie, then finished with his back-to-back birdies on the 16th and 17th to reach 13 under.

Only four other players have reached 10 under or better at any point in a U.S. Open — Morgan, Woods, Jim Furyk at Olympia Fields in 2003 and Ricky Barnes at rain-soaked Bethpage Black in 2009. None of them got there after only two rounds, much less the 26 holes it took McIlroy. As for 13 under?

"I didn't see 13 under on this golf course after any day," Snedeker said.

McIlroy's only mistake came on the last hole. From the left rough, McIlroy was aiming for the front right portion of the green away from the water. He turned it over just enough for the ball to bounce off the bank and into the water, and he failed to get up-and-down.

He lost two shots, but not his perspective.

This was golf at its absolute best, and the scoreboard showed it. Congressional was softened by overnight rain, which was obvious with the "splat" from balls landing on the green, instead of bouncing hard and into the rough as they so often do in this major.

But the measure of great golf not always comes from the leader, but those chasing him. What made Woods' record win at Pebble Beach so impressive is that he finished at 12-under 272, and no one else was better than 3-over par. Such was the case at Congressional. Among those who had finished 36 holes, only seven other players had managed to break par, and no one was within nine shots of McIlroy.

"He's decimated this U.S. Open golf course, and this is no easy test," defending champion Graeme McDowell said. "It's an amazing display of golf."

In the last 14 rounds at the majors, McIlroy has been atop the leaderboard six times.

He has been in the lead after every round except the one that matters.

"I've played two really good rounds of golf, but I know I have to play another two really good rounds of golf if I want to win this tournament," McIlroy said. "So that's all I can really think about."