Spencer Levin shot a three-under-par 69 to lead by one at the end of the third round of the Memorial Tournament as Tiger Woods battled to stay in contention.
On a day when low scores were few and far between at Muirfield Village - only 14 of the 71 remaining players went below par - Levin carded four birdies and an eagle against three bogeys to sit eight-under overall, a stroke ahead of overnight leader Rory Sabbatini.
But it could have been even better for Levin, who turned in 32 and was five under for his round after 10, before bogeying the 12th and 16th.
"I had some really good breaks, so I'll take it," Levin told pgatour.com. "I played pretty solid, but it's nice to have a couple good breaks.
"But if you're going to shoot the low round of the day out here on the Tour, or any day, you're going to have a couple good breaks or make long putts or chip in generally."
Sabbatini was one under today to lie seven under overall, two strokes ahead of Rickie Fowler and three ahead of Woods.
While Fowler equalled Levin's best-of-the-day 69 with four birdies and a bogey, Woods carded four bogeys on the back nine to more than cancel out his three birdies in a one-over 73.
"I certainly probably shot the highest score I could have shot today considering the way I hit it," Woods said.
"But I'm only four back, and out here with the conditions, supposed to be like this tomorrow again, anything can happen."
Sweden's Henrik Stenson was leading the European challenge as a 71 left him three under, alongside Japan's Ryo Ishikawa and American Jonathan Byrd.
First-round leader Scott Stallings was in a group seven on two under after a 75, while England's Justin Rose was level par and a trio of his compatriots - Brian Davis, Greg Owen and world number one Luke Donald - were three over.
Collated third round scores & totals in the USPGA Tour the Memorial Tournament presented by Nationwide Insurance, Muirfield Village GC, Dublin, Ohio, United States of America
(USA unless stated, par 72):
208 Spencer Levin 67 72 69
209 Rory Sabbatini (Rsa) 69 69 71
211 Rickie Fowler 71 71 69
212 Tiger Woods 70 69 73
213 Ryo Ishikawa (Jpn) 72 70 71, Jonathan Byrd 71 70 72, Henrik Stenson (Swe) 74 68 71
214 Aaron Baddeley (Aus) 69 72 73, Vijay Singh (Fij) 72 73 69, Scott Stallings 66 73 75, Kyle Reifers 71 70 73, Andres Romero (Arg) 69 73 72, Daniel Summerhays 69 71 74, Ryan Moore 70 73 71
215 Dustin Johnson 71 71 73, Jim Furyk 72 68 75, Matthew Every 69 75 71, David Hearn (Can) 70 75 70
216 Kevin Stadler 72 73 71, Trevor Immelman (Rsa) 71 70 75, Justin Rose (Eng) 73 72 71, David Mathis 71 71 74
217 Erik Compton 67 75 75, Lucas Glover 74 68 75, Davis Love III 74 72 71, Stewart Cink 71 73 73, Blake Adams 69 77 71, Bo Van Pelt 73 69 75, Johnson Wagner 72 72 73, Troy Matteson 72 69 76
218 Steve Stricker 73 70 75, Brendon De Jonge 73 71 74, Charl Schwartzel (Rsa) 73 72 73, Chris Di Marco 73 72 73, Ryuji Imada (Jpn) 75 72 71
219 Brian Davis (Eng) 73 72 74, Rodney Pampling (Aus) 72 74 73, Pat Perez 74 73 72, Adam Scott (Aus) 70 72 77, Greg Chalmers (Aus) 71 71 77, Greg Owen (Eng) 72 71 76, Nicolas Colsaerts (Bel) 72 74 73, Ernie Els (Rsa) 70 75 74, Luke Donald (Eng) 71 73 75, Cameron Tringale 72 74 73
220 Ricky Barnes 72 72 76, Chris Kirk 75 70 75, Seung-yul Noh (Kor) 72 73 75
221 Charlie Wi (Kor) 71 75 75, Brendan Steele 72 75 74, J.B. Holmes 72 75 74, Ben Crane 72 75 74, Branden Grace (Rsa) 74 72 75, John Huh (Kor) 71 74 76, Nick O'Hern (Aus) 74 73 74
222 Hunter Mahan 72 73 77, Jeff Overton 72 72 78, K J Choi (Kor) 74 71 77, Marc Leishman (Aus) 72 75 75, Jhonattan Vegas (Ven) 74 73 75
223 Bud Cauley 70 76 77, Jimmy Walker 72 73 78, Fred Couples 74 73 76
224 Robert Allenby (Aus) 73 74 77, Geoff Ogilvy (Aus) 71 74 79, Mark Wilson 70 76 78
225 Scott Piercy 70 75 80
226 Robert Garrigus 71 76 79, Brandt Jobe 73 74 79, Harris English 71 75 80
229 Camilo Villegas (Col) 73 74 82Starting the day four off the lead, the former world number one birdied the second hole after a fine approach to eight feet but it was the fifth where his round sparked into life.
With two par-fives in the space of three holes, Woods took full advantage by birdying both as well as the intervening sixth.
He gave one shot back at the eighth when a 40-foot putt broke too far, and after losing another at 10 it looked as though his charge would not materialise.
But he had other ideas, with three birdies in the last four holes including the shot which Nicklaus himself, watching at greenside, said was the best he had seen at the Muirfield Village course.
And Woods told Sky Sports 1: "I knew if I hit it short it would have been down and left, if I hit it long it was in the water.
"The lie wasn't all that great, I had to take a cut at it and it came out just perfect."
Only Sam Snead, on 82, now remains ahead of him in the all-time table for tour wins.
And Woods - 10 years younger than Nicklaus when he recorded his last win - said: "It's been pretty nice and to do it at age 36, it's not too shabby.
"I've been very proud what I've done so far in my career and I feel I've still got a lot of good years ahead of me."
On today's round as a whole, he said: "Boy, I hit it good today.
"I never really missed a shot, I had the pace of the greens really nice and made a few putts."
Overnight leader Spencer Levin opened up with an 11-foot putt for birdie and was solid for the remainder of his front nine, but bogeyed the 10th and gradually unravelled on the way home.
Sabbatini was one over for his front nine but hit his approach at the par-five 11th to three feet and holed out for birdie.
He repeated the feat at the tricky short 12th - and also saw Levin dump his tee shot in the back left bunker, which seemed to derail the erstwhile leader's challenge.
It led to a bogey and worse was to follow at the next as a six-foot bogey putt dived dramatically right, the resulting six dropping him three shots off the lead at five under.
Sabbatini was fortunate to see his tee shot at the next pull up just short of the water and he capitalised with a perfectly measured approach which followed the contours of the green round towards the hole - but his birdie putt stopped inches short.
He was two clear at that stage but Woods was not finished and birdied 15 before producing the big moment of the day at the next.
Levin held his breath as a par putt at 16 horseshoed round the back of the hole before succumbing to gravity, but he could not hole out at 17.
Woods' nerveless putt for a closing birdie meant he would have been out of the hunt in any case, and left Sabbatini needing an improbable eagle at the par-four 18th to force a play-off.
That was never on the cards, and Woods' coronation was confirmed moments later.
Andres Romero came from off the pace to share second place with Sabbatini, eagling the long 15th before finishing with a birdie three.
Levin shared fourth with Daniel Summerhays on five under, the latter carding 69 including three birdies and an eagle in his last five holes.
Two more Americans, Matt Every and Jonathan Byrd, were four under, with Justin Rose three under and a closing 67 leaving fellow Englishman Greg Owen a further shot back alongside Ryo Ishikawa and Aaron Baddeley. Luke Donald was one under.
Woods' playing partner Rickie Fowler's anticipated challenge crumbled spectacularly.
The young American wore his trademark all-orange for the final day but would have wanted to disappear from view after squandering an opening birdie by dropping four shots over the next three holes.
He birdied the fifth but two more bogeys followed as he recorded only one par in his first eight holes, and his woes continued on the back nine.
He ended up 12 over for his round, with three double-bogeys along the way, and seven over for the week.
