* Lingmerth, Dufner bogey final hole to shoot seven-under 65
* Spieth one shot behind
* Johnson endures miserable day on greens (Updates at end of round)
June 1 (Reuters) - Swede David Lingmerth and American Jason Dufner emerged from hibernation to share the first round lead at the Memorial tournament on Thursday as world number one Dustin Johnson stumbled with a six-over-par 78 in Dublin, Ohio.
The 2015 champion Lingmerth, who has not posted a top-10 finish on the PGA Tour this season, conjured some old magic on one of his favourite courses to card a 65 at pristine Muirfield Village.
He plundered an eagle and eight birdies but also had three bogeys, while Dufner was flawless until the par-four 18th, where he missed the green with his approach shot for the first time all day, leading to a closing bogey.
Lingmerth and Dufner led Americans Jordan Spieth and Daniel Summerhays by one stroke on a day when Johnson endured a nightmare on the greens, taking 35 putts and not making a single birdie.
Johnson’s round was marred by a triple-bogey at the par-three 16th, where his tee shot found the pond guarding the green, before he compounded his misery by three-putting.
Lingmerth had no such problems: “I caught some breaks when I missed the fairway and still had some fairly good opportunities from the rough,” he told Golf Channel.
“I consistently put myself in good spots around the greens and was able to roll a few in. I felt good with the putter today and that really helps a lot out here.
"Every time I’ve showed up here I’ve had good feelings about this place. I really love the greens.”
However, since Lingmerth has struggled this season, he did not want to read too much into one excellent round.
“It’s a very humbling game. I’ve been working hard all year and the results haven’t really been there but I've been sticking with it. There’s a lot of work ahead this week and (in) weeks to come obviously so I’m just trying to take one shot at a time.”
Co-leader Dufner has also had a quiet season, with just one top-10, but one would not have known it by the way he dismantled Muirfield Village.
“Everything,” the 2013 PGA Championship winner said, when asked what he had done well.
“I hit a lot of fairways, lot of greens, which gave me a lot of opportunities. I’ll take it. Sixty-five to start the tournament is a good place to be.”
Spieth has also found form recently.
“It was a good fight. I hung in there,” said the 2015 U.S. Open champion, who finished equal second at Colonial Country Club in Fort Worth last week.
“My wedge play was awesome last week and it continued this week. We were pin-seeking with some of the wedges.”
The Jack Nicklaus-founded Memorial tournament has attracted a stellar field as usual in what for many players is a final tune-up before the U.S. Open, with Johnson set to defend his title at Erin Hills in Wisconsin in two weeks' time. (Reporting by Andrew Both in Cary, North Carolina; Editing by Ian Ransom)