Johnson surges one ahead at the Memorial
Dustin Johnson hits his tee shot on the 14th hole during the first round of The Memorial Tournament.
Ohio - Jordan Spieth and Rory McIlroy made erratic starts
While former world number ones Jordan Spieth and Rory McIlroy made erratic starts, long-hitting American Dustin Johnson charged into a one-shot lead at the Memorial Tournament in Dublin, Ohio, on Thursday.
Taking advantage of pristine conditions with a superb all-round game at leafy Muirfield Village, Johnson racked up 10 birdies and two bogeys in the opening round of the prestigious event hosted by Jack Nicklaus.
Johnson briefly got to nine under with four consecutive birdies on his back nine but he bogeyed the par-four 17th after hitting his second shot into a greenside bunker before posting an eight-under 64, one ahead of compatriot Brendan Steele.
Australian world number one Jason Day was among a group of five players who opened with 66s, second-ranked American Spieth carded a 70 and third-ranked Northern Irishman McIlroy mixed six birdies with three bogeys and a double to return a 71.
Johnson, a nine-times winner on the PGA Tour whose best finish this season was a third place at the Houston Open in April, set the tone with an explosive birdie-birdie-birdie start.
"I just played well right out of the gates," Johnson, 31, told reporters. "I hit great shots in the right spot on the greens and rolled in some putts.
"This year, I've felt like I'm playing well. I just haven't quite played up to my potential. With me, it has everything to do with the putter. I rolled it well today."
Ohio-based Day, who clinched his third PGA Tour victory of the season at the Players Championship last month, was delighted to make a good start at a venue where he has struggled in the past.
"I hit it nice from tee to green, gave myself opportunities on the greens and then also capitalised on those," he said.
Spieth, who landed his eighth PGA Tour career win at the Colonial tournament on Sunday, relied on his usually brilliant putting to offset an iffy display with his approach shots.
"I felt awesome on the greens," Spieth said after a round that included five birdies and three bogeys. "Just missed a lot of greens.