Kiradech Aphibarnrat (Thailand) drives on the ninth during the first round of the WGC - HSBC Champions at Sheshan International Golf Club. Photo: Andrew Redington/Getty Images

Paul Dunne’s got his bid to break into the top 50 in the world off to an ideal start when he made six birdies in an opening 67 to lie just three shots behind leader Brooks Koepka on his debut in the $9,750,000 WGC HSBC Champions in Shanghai.

The Greystones man, currently ranked 81st in the world and 12th in the Race to Dubai, finished the opening day in a six-way tie for sixth place with Englishman Justin Rose, local favourite Ashun Wu and American pair Tony Finau and Matt Kuchar on five-under-par.

US Open champion Koepka carded an eagle and seven birdies on his way to a brilliant eight under par 64 to lead by a shot from Thailand’s Kiradech Aphibarnrat and current Asian Tour Order of Merit leader Gavin Green of Malaysia.

South Africa’s Haydn Porteous and Patrick Reed of America are at tied fourth on six-under-par.

Ten players share 11th, four off the pace, including Spain’s Rafa Cabrera Bello, Englishmen Matthew Fitzpatrick, Tyrrell Hatton and Matthew Southgate and Henrik Stenson of Sweden.

Dunne birdied the second, fifth and sixth and picked up three more shots at the 11th, 13th and 14th before dropping his only shot of the day at the par-three 17th.

Kiradech Aphibarnrat

“Yes, it's the way to open the World Golf Championships – seven under, really pleased with the way I'm playing.

“It's all about putting. I didn't hit the ball well. I didn't bring my A game out today, but my putting is fantastic. I holed almost every putt on the greens. My iron play is really sharp at the moment, but today I'm saying I hit a lot of greens but not good as I did the last couple weeks.

“I just tried to enjoy my game and tried to enjoy this big event in Asia, especially with a lot of top players in the field.”

Brooks Koepka

“I thought we played really well. Putted very well. One little hiccup and I three-putted from about, I don't know, three and a half or four feet.

“I felt like I started really well. Drove it really well. Any time you're making putts, and you're keeping it in the fairway, you're going to shoot good.

“I had some fun in the water (on the eighth). It was an interesting hole, to say the least. It was an awful three iron. I hit it in the water and to be lucky enough to actually get it out, was very fortunate, and then to hit three wood in there to 15 feet and then make the putt, we were laughing. It was almost kind of like destiny to make that putt for how lucky we were that whole hole.”

Haydn Porteous

“I wasn't in until a week, two weeks ago, and when I came out here, the plan was to expect nothing and take everything. Just go out there and free it up, and a few putts went in. I found a really good golf swing for the week, and hopefully, I can carry on with the same sort of form.

“I made a few really good putts out there, especially the knee wobblers from five feet and in, which was pretty solid. Kept the momentum going with some good par saves and made the birdies that I needed to make, especially on the par fives.”

Justin Rose

“It's a good start. I played really, really well today. I drove the ball exceptionally well, which is obviously what I need to do around here. I gave myself a ton of chances. I had loads of putts that just slipped by the edge.

“Five under is good, but it’s one of those days. I left a few out there, but that's encouraging. First round back after a month or so, so to get under par and a solid start, very, very happy.”

WGC-HSBC Champions, Sheshan International Golf Club (Par 72), Shanghai, China

Detailed scores

64 B Koepka (USA),

65 G Green (Mas), K Aphibarnrat (Tha),

66 H Porteous (RSA), P Reed (USA),

67 Paul Dunne (Irl), J Rose (Eng), M Kuchar (USA), T Finau (USA), W Ashun (Chn),

68 D Johnson (USA), M Southgate (Eng), R Cabrera Bello (Esp), P Cantlay (USA), H Stenson (Swe), B Harman (USA), T Hatton (Eng), M Fitzpatrick (Eng), M Griffin (Aus), D Berger (USA),

69 C Kim (USA), P Khongwatmai (Tha), J Smith (Eng), C Reavie (USA), A Hadwin (Can), H Ryu (Kor), D Lipsky (USA), J Day (Aus),

70 H Swafford (USA), J Vegas (Ven),

71 K Stanley (USA), M Lorenzo-Vera (Fra), Z Xinjun (Chn), D Kataoka (Jpn), B Wiesberger (Aut), B Haas (USA), A Levy (Fra), S Kim (Kor), M Leishman (Aus), X Schauffele (USA), T Fleetwood (Eng), P Mickelson (USA), S Hend (Aus), R Fox (Nzl), P Casey (Eng), L Glover (USA), D Zecheng (Chn),

72 C Howell Iii (USA), P Uihlein (USA), S Chawrasia (Ind), L Yanwei (Chn), P Perez (USA), S Imahira (Jpn), J Rahm (Esp), L Haotong (Chn), L Wenchong (Chn), A Noren (Swe), A Scott (Aus), H Tanihara (Jpn), T Olesen (Den),

73 F Zanotti (Par), R Ramsay (Sco), C Schwartzel (RSA), P Saksansin (Tha), R Sterne (RSA), M Hendry (Nzl),

74 A Hall (Aus), H Matsuyama (Jpn), A Dodt (Aus), B Grace (RSA), C Yi (Chn),

75 R Henley (USA), T Pieters (Bel), G Storm (Eng),

77 W Bryan (USA), F Molinari (Ita), R Fisher (Eng),

78 B Stone (RSA).