Now, can he keep it going?
McIlroy took advantage of prime scoring conditions to shoot a 6-under 66 on Thursday, putting him in what has become a familiar position: the first-round lead.
McIlroy has played the opening round in a cumulative 55-under par this year, including three 63s and a course-record 64 at last week's Scottish Open. But he's failed to win any of those events, largely because of what he calls his "second-round thing."
His total score on Fridays -- 15 over.
"Maybe it's having higher expectations going out on a Friday because you shot a low round," said McIlroy, whose goal now is "to put those expectations aside."
For the early starters, it couldn't have been better day for scoring -- mild and sunny, with only a slight breeze rippling the flags. It was a far cry from 2006, when Tiger Woods won on a dry, fiery course that made the grass more brown than green. This time, Royal Liverpool was lush and relatively soft after intermittent rain on Wednesday.
Matteo Manassero made only one bogey and also shot 33 after the turn, taking advantage of a quirk in the course which puts three par-5s in the closing nine. He birdied them all for a 67.
He wasn't the only Italian off to an encouraging start. Brothers Edoardo and Francesco Molinari opened with matching 68s.
"I saw the leaderboard," said Francesco, the younger of the siblings. "But it's a tough course, so you have to focus on what you are doing rather than the others are doing -- even if it's your brother."
Also at 68 were Spain's Sergio Garcia and a pair of Americans, Jim Furyk and Brooks Koepka. Another shot back, Woods was joined at 69 by countrymen Rickie Fowler, Jimmy Walker and Boo Weekley; Japan's Hideki Matsuyama, Koumei Oda and Yoshinobu Tsukada; Sweden's Robert Karlsson; and Australia's Marc Leishman.
"I didn't play fantastic, but the course is out there to make some birdies on," said Karlsson, who teed off in the first group of the day at 6:25 a.m.
He described the breeze as "tricky," but acknowledged it wasn't much of a defense against those going out in the morning.
"I'll take this tricky," Karlsson said.
The wind picked up through the day, making things tougher for those with afternoon tee times.
Even so, Adam Scott made a run at the leaders, spurred by an eagle at the fifth. The world's top-ranked player staggered a bit coming to the finish but still managed a 68, matching Garcia and company.
Of the top 17 players in the clubhouse, Scott and Weekley were the only ones to tee off in the afternoon.
"We had perfect scoring conditions," McIlroy said. "There were plenty of opportunities to make birdies."
Defending champion Phil Mickelson, who hasn't won since his 2013 victory at Muirfield, was among those who faded late in the day. He shot 74, closing with a bogey after his second shot sailed out of bounds, forcing him to take a cart back to the spot where he struck the ball for a do-over.
Ernie Els really made a mess of things, the tone set when his very first shot struck a fan in the face. Clearly unsettled, the Big Easy missed a putt of less than a foot at No. 1, then sloppily whacked the ball with a backhanded swipe and missed again, making triple-bogey.
Woods has gone six years without a major title and this season was interrupted by back surgery on March 31. He missed the Masters for the first time, and then the U.S. Open, before returning three weeks ago at Congressional. He missed the cut by four shots, though he was happy that he felt no pain.
On Thursday, he shot a 3-under 69.
Woods' threesome included Sweden's Henrik Stenson, who is among four players with a shot at replacing Scott at No. 1 in the world if he wins. The others are Justin Rose, Bubba Watson and Jason Day.
Woods was No. 1 when he took three months off to heal his back. Now he's seventh.
The past three Open champions have all been in their early 40s. Koepka, a 24-year-old American who began his pro career in Europe, wants to end that streak.
"I hope someone in their 20s wins," he said. "I hope it's me."
The Associated Press contributed to this report.
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