Spencer Levin holds a one-stroke lead heading into Sunday's final round at the PGA Tour Memorial Tournament in Ohio, while Aaron Baddeley dropped off the pace.
The 27-year-old American survived a tough third day, with strong wind and firm conditions, to register a three-under-par 69, and reach eight-under overall for the competition at Muirfield Village Golf Club.
He is one shot ahead of second-round leader Rory Sabbatini, who bogeyed three of his first six holes to card a one-under 71 on Saturday.
"I don't know if I could have done much better," Levin said.
"I had some really good breaks, so I'll take it. I played pretty solid. This is what I've dreamed of ... to be in the lead of a tournament, especially Jack's tournament," he added, referring to course architect and golfing great Jack Nicklaus.
"This is one of the biggest tournaments on the tour. You couldn't put yourself in a better position."
Levin's fellow American Rickie Fowler, the 2012 Wells Fargo champion, birdied two of his last four holes to finish with a three-under 69, while four-time winner Tiger Woods posted a one-over 73 to sit fourth at the close of play.
Fowler is outright third at five under, one stroke ahead of Woods, who carded four bogeys on a disappointing back nine.
"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."
Australian Aaron Baddeley turned in a one-over 73 for his third round to retain a slim chance of contending on the final day.
He shares eighth place at two under, alongside with Fiji's Vijay Singh, Argentine Andres Romero and Americans Kyle Reifers, Daniel Summerhays and Scott Stallings.
The next best Australians are Rod Pampling, Greg Chalmers and Adam Scott, all tied 36th at three over.