Rory McIlroy shrugged off a closing three-putt bogey and declared his opening 67 in the WGC-Bridgestone Invitational with new bagman Harry Diamond as the start of a new chapter in his career.

Despite hitting a wedge 50 feet past the pin at his final hole and then missing from four feet for par, McIlroy looked close to best as he finished just two shots behind early leader Thomas Pieters at Firestone Country Club.

There were a few incidents of mis-clubbing and a couple of mishits. But as he was pulling the clubs, double-checking his yardages and hitting all the shots, he took those errors on the chin and insisted his game is trending in the right direction as he counts down to the final major of the season next week

“There were a couple of times where I probably should have hit another club, but that’s on me, that’s not on anyone else,” McIlroy said. "So I'd much rather be frustrated at my own decision than someone else's." 

After finishing close to the top of the putting statistics at The Open, McIlroy holed 106-feet of putts and used the blade just 26 times as he made five birdies and two bogeys in a three-under par opening round.

Playing partner Jordan Spieth, the Open champion managed 140 feet after draining consecutive putts from 33 feet and 52 feet on their back nine. 

But he also shot 67 to leave them two strokes behind early leader Pieters, whose 65 gave him a one-shot lead over Russell Knox as McIlroy and Spieth shared third with Kevin Kisner, Ross Fisher, Bubba Watson and Jon Rahm.

"It was good," McIlroy said of a round in which he scrambled six times out of seven for par. "I kept in good spirits out there and it was good to have my best friend on the bag. 

"It's different. You are hearing a different voice. But I stuck to it today pretty well and I guess it's the start of a new chapter in my career and we'll go from here."

Starting on the back nine, McIlroy rolled in a birdie putt from 26 feet at the 11th to continue the good putting streak he began at Royal Birkdale with a share of fourth behind Spieth.

One of his biggest problem in recent seasons has been his erratic wedge play  and he admitted he’s looking to sharpen up that aspect of his game before next week's US PGA at one of his pet venues, Quail Hollow

“Just good signs in my game,” he said of his ambitions for the week. “Go out and hopefully see little improvements as the week goes on. 

“Obviously I would love to win, I would love to go into next week with a lot of confidence. But I feel like my confidence is building. I just need to see my game get a little bit sharper, especially the wedges.”

What pleased him most was his putting, especially over the last 11 holes.

"I've been working hard at it, trying to blend something I have been working on with a little bit of feel as well and I feel like it is coming together," McIlroy said. 

“I think I finished fourth in the stats at Birkdale and obviously had a good putting day today.

"So it's definitely moving in the right direction and definitely something to build on."

A par putt from 10 feet at the 17th seemed to inspire him and after made a four footer for birdie at the 18th to turn in one under,  he was more impressive on his back nine.

After getting up and down from sand short of the green at the par-five second for another birdie, he then hit another wedge to four feet at the third to move within one stroke of the lead on three-under.

If the par putt he made on the 17th was huge for his confidence, the 18 footer he made for par at the fourth, where he pulled his approach 30 yards left down a slope but escaped unscathed, was even bigger.

Having watch Spieth hole a 33 footer for birdie at the fifth, McIlroy looked on as The Open champion made another from 50 feet at the sixth and promptly rolled in a 13 footer of his own there to move to four-under.

Looking forward to building momentum for a crack at a fifth major title at Quail Hollow in next week’s US PGA, he was happy with his start.

“It would have been nice to finish four-under but with how I hit it and some of the up-and-downs I made, 67 was a fair reflection of how I played,” he said.

Rory McIlroy

“It's a golf course I've always enjoyed since the first time I came here in 2009. I always felt like it was a golf course that suited me and I could play well on. It was nice to get back, nice to see some putts go in and shoot a decent score to get off to a good start this year's tournament.

“It was good with Harry on the bag - a little weird at the start. Obviously, it's been nine years since I've had anyone else on my bag, so even just hearing a different voice, it's a little different.

“But I thought we did well out there, sort of consulted each other when we needed to. I sort of did all my own stuff when I felt like I was good and then whatever decisions I made, whether they were good or bad, it was on me. I didn't have anyone to get frustrated at or than myself. So it went well out there.  

“It could have been a really low score, but I played okay - I don't feel like I played really good. I drove it well, but I shot 67 in one of the biggest golf tournaments in the world. It's there, it’s just a matter of repeatedly doing that and being a little bit more consistent.

“I think 67's a fair reflection of how I played. It could have been better, but it could have been worse. I made some good putts for pars, made a couple of key up‑and‑downs around the middle of the round, so I think 67's a fair reflection of how I played. I holed some good putts, so yeah, I was pretty happy with it."

Thomas Pieters

“I only had two putts from above the hole. The rest of them were just pretty straightforward putts. I think that was the key. I was pretty terrible from the tee, but managed to find a lot of greens today. I think I hit eight or nine in a row on the first nine and that was important as well.  

“It was kind of a stress‑free round. On my back nine, I missed a couple of greens but got up and down a couple times, so I’m pretty happy.

“I had a fun round with Adam and Sergio, just having fun. I don't get too much into where I have to hit it, where not to, mapping it out. I leave that to my caddie and we figure out a simple game plan and try to stick to that.

“Obviously I like the course. I've never been, but it's just a golf course. You have to plot your way around and manage the game plan that works for you.

“I've had good results this year. I've been in contention and that's all I want to do. I just haven't had that win. I feel like if I had a win already this year, my year would have been good, but I just haven't finished it off.  

“I still have plenty of tournaments to go, but even if I get myself in contention ten more times and don't win, that's all you want to do. Of course, you have to finish it off, but I'll learn that along the way.”

Russell Knox

“I hit the ball great today. I've obviously struggled a little bit recently but my game's not been far off. I know it hasn't been. I made a couple of adjustments in my equipment, which is going to be important moving forward for me. Today was how I normally have played. I'm very happy to have shot four under.

“I went back to the putter that I used when I won in China. I figured it did work at one point, so it worked today. I rolled the ball beautifully. I switched iron shafts, which I haven't done in five years. That seemed to make it a little easier for me.

“I know my world ranking has slipped a bit, I think I'm 50 now and obviously being in the top 50 is a big deal for anyone. So I put pressure on myself to be in the top 50. I feel like when I'm playing well, I'm a top 20 player.”

Scores:

65 Thomas Pieters

66 Russell Knox

67 Kevin Kisner; Ross Fisher; Bubba Watson; Jordan Spieth; Rory McIlroy; Jon Rahm

68 Jimmy Walker; Andres Romero; Dustin Johnson; Charley Hoffman; Adam Hadwin; Adam Scott

69 Kyle Stanley; Jhonattan Vegas; Hideki Matsuyama; Alex Noren; J.B. Holmes; Paul Lawrie; Zach Johnson

70 Bernd Wiesberger; Brian Harman; Scott Hend; Hudson Swafford; Xander Schauffele; Paul Casey; Harold Varner III; Charl Schwartzel; Bill Haas; Rickie Fowler; Tommy Fleetwood

71 Francesco Molinari; Shaun Norris; Branden Grace; Renato Paratore; Jason Day; Brooks Koepka; Phil Mickelson; Matt Kuchar; Thongchai Jaidee; Daniel Berger

72 Lee Westwood; Wesley Bryan; Emiliano Grillo; Pat Perez; Tyrrell Hatton; Henrik Stenson; Justin Rose; Sergio Garcia; Kevin Chappell; Andy Sullivan

73 Brendan Steele; Thorbjørn Olesen; Si Woo Kim; Ryan Moore; Rod Pampling; Matthew Fitzpatrick; Justin Thomas; Satoshi Kodaira; Marc Leishman

74 Jeunghun Wang; Sam Brazel; Gary Woodland; Louis Oosthuizen; Hideto Tanihara; Fabrizio Zanotti; Mackenzie Hughes

75 Bryson DeChambeau, Chris Wood, Russell Henley; Patrick Reed

76 Danny Willett; Billy Horschel; Rafa Cabrera Bello; Jason Dufner.