Damien McGrane and Shane Lowry bagged a spectacular combined haul of 14 birdies in a sensational head-to-head scrap for the first-round lead in the The Ballantine's Championship.
Yet, incredibly, the duelling Irishmen would still wind up six strokes apart at day's end in Icheon, South Korea.
As Kells man McGrane (40) skipped into a one-stroke tournament lead on six-under, Lowry haemorrhaged half a dozen shots on his final six holes.
After signing for a level-par 72, the Clara native ended up frustrated in a tie for 36th with, among others, world No 1 Lee Westwood and Belfast's Gareth Maybin.
Following his impressive final 54 holes at last weekend's Volvo China Open, McGrane's superb 66 on a strategically demanding Blackstone course yesterday made nonsense of odds of 200/1 offered against him at The Ballantine's.
The key was McGrane's short game, especially his putting, as he stirred memories of his sole European Tour victory in China three years ago and last October's hugely impressive charge into second place behind Graeme McDowell at the Andalucia Masters in Valderrama.
Several pin placements on Blackstone's wickedly sloping greens were savage, but McGrane was oblivious to it all as he racked up eight birdies, including a fantastic chip-in from the rough 20 yards to the right of the second.
Revelling on surfaces running at around 10 on the stimp, McGrane said: "I'd good pace on my putts, which is important. I holed everything inside 15 feet, made plenty of birdies so I'm very satisfied with that.
"The two bogeys I made came out of nowhere really but that's golf.
"I'm happy to have made such a good start but I've got to keep it going. The fairways are generous and, like last week, there're plenty of birdie chances out there, so scoring will be quite low."
Asked how he found the strenuous up-hill, down-dale journey around Blackstone, McGrane chuckled: "You just have to put your head down and pump those legs as best you can and hopefully you'll see the top!"
However, it can't have been easy for his beefy six-foot playing companion Lowry to haul his 16-stone frame around the heavily undulating course.
Playing his best golf by far since returning from a broken wrist last month, Lowry (24) took a commanding lead as he landed six birdies in a faultless first 12 holes. His chip-in birdie at three (his 12th) was reminiscent of a sensational weekend in Baltray two years ago when he won the Irish Open as an amateur.
Yet Lowry's day began to darken at four, where he needed to make a great up-and-down for bogey after hitting his second into water. This was followed in quick order by an untidy six at the long fifth and a calamitous triple-bogey seven at the next. Another dropped shot at eight brought Lowry back to level par.
"Well that was an interesting day," he tweeted. "Six birdies for level par -- not what the doctor ordered but there's always tomorrow."
Michael Hoey dropped shots in the final five holes of his 71 to share 19th place on one-under with Paul McGinley, who birdied two of his final four.
Westwood and playing companions Ian Poulter and Miguel Angel Jimenez were constantly bothered by clicking cameras and cell phone ring tones yesterday, the world No 1 dropping his club in fury at the par-three seventh when one went off on his downswing.
"You couldn't make any more noise if you tried," Westwood said pointedly to fans standing behind the tee as his shot arced into the left greenside bunker, from which he made bogey four.
Westwood then stumbled to a dreadful double-bogey six at the ninth, his final hole, after hooking his tee shot into a fairway bunker; slapping his next into a plugged lie in sand short of the green before taking two to get out. His teeth were tightly clenched as he signed for a 72.
Poulter did relatively well to recover from a disastrous opening two double-bogeys to shoot 74, while Jimenez had to be satisfied with a bogey-free 70.
Ernie Els has taken a lot of stick from colleagues since switching to a belly putter and it hardly seemed worthwhile yesterday as he racked up 34 putts on his way to a 73.
The Ballintine's Championship,
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