Rory McIlroy completed his incredible comeback with a battling 68 at Royal Birkdale and insisted: "This was the round that got me back into the championship."

After playing his first nine holes in five-over on Thursday, the 2014 champion was six-under for the next 27 holes as he defied crosswinds gusting to 35mph and four birdies and a sensational run of par saves in a two-under par second round.

It was another mesmeric performance from the Holywood star, who made three birdies in his first six holes to be eight shots better than he was for the same stretch on day one.

What pleased him most was a series of Houdini-like escapes on the back nine, saving three clutch pars in a row at the 10th, 11th and 12th before following bogeys at the 13th and 15th with another chip and putt birdie at the 17th.

After finishing just three shots behind clubhouse leader Matt Kuchar on one-under a beaming McIlroy said: “To be in after two days and be under-par for this championship after the way I started, I’m ecstatic with that. I'm very happy. I think anything around even par today is going to be a great score."

He even admitted that his 68 shaded Thursday's 71 in terms of importance, adding: "They're both huge rounds for very different reasons. 

"But this was definitely the round that got me back into the championship.

"That stretch, 10, 11, 12, just to keep the momentum going and keep the round going, those saves were all huge. I don't think any one was more important than the other, but all three together were massive."

McIlroy started sensationally by blasting a three-wood 372 yards down the first before chipping just three feet to set up a birdie.

He then hit a great second to eight feet at the third to move into red figures before hitting another corker to four feet at the tough sixth to go three under for the day.

He said: "I played the first six holes in what, eight shots better than I played them yesterday?

"So, yeah, there was a lot of quality out there, and I was happy to see that. I just have to try to keep that going for the next two days.

"To birdie three of the first six and give myself that little bit of a cushion to play with was nice."

Out in 31 to move up from 58th overnight to tied ninth, the key to his round came at the 10th, 11th and 12th, where he made three crucial par saves in a row to remain in control.

At the 10th, he drove into sand up and after getting back into play, fired a wedge to 12 and gave a huge, clenched fist celebration as he sank the putt for his four.

After making a 15 footer down the hill for another clutch par at the 11th, he splashed out to three feet from a pot bunker at the par-three 12th and saved par again.

Describing that stretch as "huge", he added: "I made some key up-and-downs at the start of the back nine. 

"They're the putts that haven't quite been going in over the past few weeks. 

"That's all it takes to keep a round going, and to see those putts go in on 10 and 11 gives me a lot of confidence going into the weekend."

His run of luck ended at the 13th — the toughest hole on the course yesterday — when he pushed his drive into deep rough and eventually tugged a seven-foot par putt wide of the mark.

It was a battle coming home, and after chipping dead to save par at the 14th, he took six at the par-five 15th after finding deep rough from the tee before getting up and down again for par at the 16th.

He then chipped to five feet at the 17th and made the birdie putt to end the day ecstatic with his 68 for a one-under par total.

What pleased him most about the first two days was the character he showed, though he tried his best to play things down with 36 holes still to go.

"Is not as if I went through war out there," he said with a grin. "It was just a round of golf. I just stay patient.

"I was very proud of myself that I hung in there and tried to stay as positive as I possibly could."

On those putts on the 10th and 11th, he added: "I guess it's almost like a validation that when you hole putts like that this is really good, you're fighting for it, and you're mentally where you need to be.

"I don't think it gives you confidence but almost more satisfaction."

With his job done, McIlroy had no plans to settle down to watch the golf.

"I've battled enough, and I've thought about golf enough today that I don't really need to see those guys out there," he said. "I'm happy to be in the clubhouse and happy to be on a good score."