The world No 1 was left frustrated after an opening 70 which included two bogeys and a double-bogey at the 17th, where his tee shot came up short and bounced back off the rocks in front of the green and ended in the water.
But McIlroy was able to build on a good start to his second round after starting at the 10th, carding three birdies in his first six holes and making further gains at the fifth and eighth while keeping a bogey off his card as he closed on eight under par.
The 26-year-old admitted he had let himself down on the greens at TPC Sawgrass last week, but he gained confidence from a 29-foot putt for birdie as his opening hole and went on to hit 14 greens in regulation, using just 29 putts for a round he described as “stress-free”.
“Anytime you can play a round of golf with no bogeys you’re doing something right,” said McIlory, who claimed his maiden PGA Tour title at Quail Hollow in 2010 following a sensational final-day 62.
In the groove
“I really found a good groove with the driver. My iron play wasn’t as sharp as it could have been, but a good score puts me right up there for the weekend. Mentally I feel very sharp. I’m not putting myself under that much stress of having to save pars or anything.
“I just know from experience what a good score is and that sometimes, if it’s just not happening, you’re not losing any ground. I felt like I could have shot 63 or 64, but I realise 67 is still a good score and puts me in position going into the weekend.”
McIlroy also insists he is a far more complete golfer than when he stormed to the title five years ago against a high-quality field including the likes of Tiger Woods and Phil Mickelson.
“Everything has changed,” he added. “I feel I’m a much better player. My stature is much higher. When I’m on the leaderboard, it carries a bit more weight.
“I’m much better prepared and equipped to be in contention week-in and week-out, more grounded and mentally much better as well.”