HOYLAKE, England - Rory McIlroy left the door invitingly ajar for a charging pack led by Rickie Fowler and Sergio Garcia before slamming it shut with a dazzling finish on Saturday to lead the Open by six strokes with one round left.
The Northern Irishman began the day four shots clear of Dustin Johnson, was reeled in by inspired American Fowler after 12 holes, but magnificent eagles at the 16th and 18th saw him disappear over the horizon with a 16-under-par total of 200 at a rain-soaked Royal Liverpool course.
It is 50 years since a player went into the fourth round of the Open with a bigger lead, on that occasion Tony Lema taking a seven-stroke advantage into Sunday at St Andrews in 1964.
Yet for much of the third round on a links course softened to perfection by stormy weather, McIlroy seemed in real danger of missing out on his fair share of the birdie feast which allowed 17 players to shoot sub-70 rounds and 35 to break par.
After 13 holes he was level par for the day and, with dark clouds brewing overhead, Fowler was breathing down his neck.
He responded with an incredible 3-3-3-3-5-3 climax to move clear and only an extraordinary turnaround on Sunday can prevent him completing a first Open triumph to add to the U.S. Open and U.S PGA titles he won in 2011 and 2012 respectively.
"I was conscious that Rickie was getting a little closer or Sergio or whoever it was," McIlroy, who would break three-times winner Tiger Woods's Open record of 19 under (set in 2000) with a round 68 or lower on Sunday, told reporters.
"But it was nice to be able to come up with the goods when I needed them the last few holes."
Should he close the deal on Sunday, the 25-year-old McIlroy will have completed three legs of the career slam on Sunday, leaving just the Masters title missing from his collection.
"I'd be in pretty illustrious company," he added.
"So not getting ahead of ourselves, here, but yeah, it would mean an awful lot. I didn't think that I'd even have the chance at 25 to go for three legs of the Grand Slam. So I'm going to try to put all of that out of my head."
Like McIlroy, Fowler also carded a four-under 68 but three bogeys over the closing five holes left him ruing what might have been as he chases a first major title.
"If I'm able to go out and get off to a good start, maybe I can put a little bit of pressure on him," Fowler, who will play alongside McIlroy in the final round, said.
"He's definitely in control of the tournament right now."
Spaniard Garcia, who hit back from a poor start in which he found two greenside bunkers at the first, is seven shots adrift in a tie for third place with Johnson after a round of 69.
Frenchman Victor Dubuisson is on eight under.
Darren Clarke, the 2011 champion, fired the day's joint best round of 67 but three-times winner Tiger Woods, who started on the 10th along with half the field, was wallowing in a distant 58th place at three over par after a rusty 73.
Last year's champion Phil Mickelson fared slightly better than his old sparring partner with a one-under 71 but his hopes of retaining the title are over.
McIlroy looked anxious early on, finding sand with his second shot at the first and then missing a par putt after an under-cooked bunker shot.
His heart was racing at the second when he badly misjudged a birdie putt and left himself an awkward return which he holed.
A birdie at the par-five fifth got him back to level par for the day but he was in trouble after driving into deep sodden rough at the long par-four seventh.
After chopping out sideways to the fairway he pitched into the green and rattled in a brave 15-foot par putt to put distance between himself and Johnson, who bogeyed.
With Fowler snapping at his heels McIlroy was unable to make another birdie until the par-four 11th, only to hand back a shot at the next hole after finding the rough off the tee.
The 14th proved crucial.
Shortly after Fowler, playing in the group ahead along with Garcia, got into trouble at the 454-yard par-four and dropped a shot, McIlroy fired in a laser-like 30-foot birdie putt and from then the shackles came off.
Sensing the perfect moment to strike a hammer blow on his rivals, he attacked the remaining par-fives with relish, eagling the 16th and 18th to huge roars from the galleries.
"It seemed like Sergio and Rickie sort of struggled down the stretch a little bit," McIlroy said. "But that could have been a completely different story. Instead of a six-shot lead it could have been a one or two. A lot can happen."
Fowler, runner-up at the U.S. Open last month and fifth at the Masters, began with two birdies and picked up further shots on the fifth, sixth and 10th before rolling in a monster putt at the 11th to reach 11 under par.
He had begun his round six shots off the lead but another birdie at the 12th, together with a McIlroy bogey at the same hole put the two tyros level at the top of the leaderboard.
Big-hitting Johnson began the day as McIlroy's closest challenger and birdied the first after a stunning wedge approach to halve the deficit but his challenge faded as he leaked shots in the rain, eventually recovering his form to sign for a 71.
The ever-popular Garcia, who has seven top-10 finishes at the Open but has never won a major, birdied the second, fifth, eighth and ninth to reach the turn in 32.
A rather disappointing back nine left him needing a huge swing on Sunday if he is to end his long wait for a major.
"If Rory plays the way he's been playing, it's difficult to see anybody catching him," Garcia said.
Play ended a few minutes before 4pm local time owing to the decision to start the players in groups of three from the first and 10th tees - a decision prompted by forecasts of torrential rain storms in the afternoon along the Liverpool coast.
Thankfully the worst of the downpours arrived shortly after the finish of play and even if it returned on Sunday it surely will not rain on McIlroy's parade. (Reporting by Martyn Herman; editing by Pritha Sarkar)