Rory keeps lead as wind gets up at Open
Australia's Adam Scott plays out of a bunker on the second hole during his second round of the British Open Golf Championship at Royal Liverpool Golf Course in Hoylake, north west England on July 18, 2014 - by Peter Muhly
The 25-year-old form Northern Ireland, chasing his first Open title after two major wins in the United States, was enjoying a restful morning ahead of a mid-afternoon tee-off time.
His opening salvo of six-under 66 gave him a one shot lead over the 155-strong field and set the target for Friday morning.
World number one Adam Scott, who started the day two back of McIlroy, had been determined to close the gap on the Irishman before he got started.
But two missed short-putts at the second and third sent him reeling and, despite a birdie at the fifth, two more dropped shots followed at the 12th and 13th, dropping him to one under.
He got one of those back at the next to move back to two under.
South African George Coetzee briefly threatened the McIlroy lead when he got to six under after 15 holes, but he promptly bogeyed the next two holes and eventually came in with a 69 for five under.
"Obviously six-under (by McIlroy) was a hell of a score yesterday," he said.
"And I didn't think it was doable today to get to that number, but when I made birdie on 13 I was like - well, all right, now I'm pretty close.
"I think I'm the top 10, and then the next one and the next one and I realised quite quickly."
After Coetzee came in, the breeze stiffened over the Royal Liverpool links, making gap-closing birdies a much-harder prospect.
American Brooks Koepka and Italian trio, Francesco and Edoardo Molinari and Matteo Manssero, who were among seven golfers grouped at four under overnight, all dropped shots early on as the watchfull McIlroy stayed ahead.
Defending champion Phil Mickelson (70) and US Open winner Martin Kaymer (72) stayed in touch for the weekend at level par and one over respectively, while top home hope Justin Rose was at one under after 16 holes.
The cut was projected to fall at two over.
Tiger Woods, playing in just his second tournament since undergoing back surgery in late March also had a mid-afternoon tee-off time after shooting a morale-boosting 69 on Thursday.
The 38-year-old American was energised by his opening efforts which saw him wrack up five birdies down the back nine after a bogey-bogey starte.
"I felt good about a lot of things that I did out there today," he said.
"Especially coming back after that start I had (two bogeys in first two holes), to fight myself back into the championship. I feel pretty good about it."