Rory McIlroy made a dream start to the third round of the PGA Championship on Saturday, but then came the wake-up call.

Vying to defend the title he won last year at Valhalla, the world No.1 surged up the leaderboard with birdies at the second and fourth before draining a 60-foot eagle putt at Whistling Straits’ par-five fifth.

But McIlroy, playing for the first time since the US Open in June, after a ruptured ankle tendon forced him out of the British Open and Bridgestone Invitational, couldn’t maintain the momentum, giving two strokes back with bogeys at the sixth and eighth.

“I guess that probably shows just a lack of competitiveness and considering this is the first week back in a few weeks,” said the 26-year-old, who carded a four-under par 68 for a six-under total of 210.

However, he was pleased to see signs of progress after posting back-to-back 71s in the first two rounds.

“I’m hitting the ball great,” McIlroy said. “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.”

Putting from the fringe at the fifth hole, McIlroy had his caddie leave the pin in.

“I’m glad I did, it was going six or eight feet past.”

“It was nice to see that one drop. As I said, dream start and a little disappointing that I wasn’t able to keep it going from then.”

McIlroy had four birdies and two bogeys coming in, capping his round with a morale-boosting 12-foot birdie putt at 18.

With the rain-softened Straits course yielding a slew of low scores, McIlroy said it was hard to stay patient.

“In a way it’s difficult not to get ahead of yourself because the course … was gettable and it was just as soft as it was on Thursday.

“With the heat and everything, the ball’s going a long way. So the course was playing quite a bit shorter than it played at the start of the week.”

While McIlroy says he is untroubled by his injured left ankle, he acknowledged that his lengthy layoff had robbed him of some sharpness.

Opting for a driver off the eighth tee was an example of a poor decision that he put down to lack of competition rounds.

“These things happen and (you) just try to learn from them and move on,” McIlroy said.

With the lead at 14-under late in the round, McIlroy said his aim on Sunday would be to set a “realistic goal and target.”

“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.”