BETHESDA, Md. — In one of those can't-miss moments in sports, thousands of fans covered the hill behind the 10th green at Congressional. They spilled onto the clubhouse veranda, pressed their faces against the windows and lined 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," golfer Ian Poulter said.
In some respects, it was better.
McIlroy, the sympathetic figure at the Masters, was as close to perfect as golf allows Friday during an assault on the record book. The 22-year-old from Northern Ireland became the first player in the 111 years 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 2009 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.
"It's very near the best I can play," McIlroy said.
Not since Woods destroyed the field at Pebble Beach in 2000 for a record 15-shot victory has anyone made golf look this easy, at least for two rounds.
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.
He tied the U.S. Open record of 12 under — reached 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,' " said his caddie, J.P. Fitzgerald.
Then came the 17th, when McIlroy hit a 7-iron from 175 yards, barely cleared the bunker and left him 15 feet below the hole for another birdie to go to 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 Bethpage Black in 2009. None of them was there after two rounds. As for 13 under?
"I didn't see 13 under on this golf course after any day," golfer Brandt Snedeker said.
McIlroy knows better than to start celebrating before Sunday. At Augusta National two months ago, 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. In the 2009 PGA Championship at Hazeltine, 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."