Still finding his way back to competitive sharpness following a five-week injury lay-off that left him inactive since the US Open in June, a fit-again McIlroy, 26, shot his best round of the week so far on Saturday as he carded a four-under-par 68 to move to six under for the tournament, six shots off the pace set by 54-hole clubhouse leader Branden Grace.

With the left ankle he injured during a football game with his mates on July 4 consigned to history, the world number one had looked primed to make a bigger move as he birdied two of his first four holes and then sank a monster 65-foot eagle putt at the par-five fifth.

Yet the rustiness from almost two month out of the game he had referenced following his second consecutive 71 on Friday, continued to affect his progress and four bogeys followed at the sixth, eighth, 12th and 15th holes. He would finish strongly with birdies following the latter two bogeys and more coming at 16 and 18 but for the Irishman it was very much a case of what might have been.

“Yeah, got off to a dream start, really,” McIlroy said. To be four under through five and not having birdied the first and third hole, to birdie four as well was a bonus.

“But to give those shots away again on six and eight, you really have to battle to shoot four under in the end. I guess that probably shows just a lack of competitiveness and considering this is the first week back in a few weeks.

“But really positive signs out there. Hitting the ball great. I putted much better today thankfully. So if I keep showing improvement each and every day like I have done, it's a good sign going into the rest of the season.”

McIlroy is set to take the next two weeks off “just to sort of reassess everything” before resuming his campaign on September 4 at the Deutsche Bank Championship in Boston, the second tournament in the end of season FedEx Cup play-offs.

He has not ruled out his chances of victory and a successful PGA Championship defence on Sunday but is taking a more pragmatic view of the the final major of the year's fourth round.

“It's all about setting a realistic goal and target. I know that the way the back nine's playing there, the leaders could be 14-, 15-under by the time the day ends. So, that would leave me eight shots back. In the back of your mind, you still think you have a chance, because that's what your competitive nature tells you. But if you're looking at it realistically, I want to go out there tomorrow and shoot the best score that I've shot this week.

“I've stood still a little on Thursday and Friday, but definitely improved today and you want to improve on that again tomorrow. If I do that, I think that, as a whole, the week would be somewhat of a success. It wouldn't be quite what I wanted, but as I said, I can take positives from it and move on.

“Just getting back into the rhythm of it, getting back, I thought it might have taken me a few weeks, but I feel like it's right there and feels like I haven't been away for that long, which is nice. I feel like I can be very competitive for the next few weeks.”