Jason Day's third-round collapse in South Carolina has opened the door for Luke Donald to finally land the RBC Heritage.
World number one Day went into Saturday with a share of first but ended it down in 40th, nine shots off the lead, after signing for an eight-over-par 79.
England’s Donald, who has three second-place finishes at Harbour Town Golf Links, recorded four birdies in his two-under 69 to take a one-shot lead into the final day.
American duo Jason Kokrak and Charley Hoffman are a shot back on six under, but Donald is well set to kick-start a season that has returned just one top-25 finish and saw him miss last week's Masters.
He picked up shots on the second, fourth and eighth before dropping one on the ninth as he reached the turn in 34. He then birdied the 10th but a bogey on the 13th dropped him back to seven under for the tournament.
Australian Day, who was looking for a third win in four events, was two over for the day after three holes, with a birdie on the second sandwiched by a bogey on the first and a double on the third.
Another birdie and a bogey followed before the turn, but he bogeyed six of the back nine.
Scotland's Russell Knox shot the best round of the week on Friday with a 65 but struggled for a two-over 73 in his third round to slip to eighth, four shots behind Donald.
Donald admitted that watching from home while Danny Willett won the Masters last week has given him extra motivation.
He told pgatour.com: “Of course it has. I certainly don’t want to be sitting on the couch watching people win Majors, especially your fellow countryman, guys I played with. Danny obviously played great but I certainly feel I have some good years in me and I’m not quite ready to resign to the couch just yet.”
On his prospects on Sunday, Donald added: “I think conditions are meant to be a little calmer, a little bit less wind. This field always gets packed. Someone will come back from in the pack and shoot a low score
“I need to go out there and play a round like I did today, not play defensive, try and make some birdies and hopefully shoot three or four under and hopefully that will be enough.”
Bryson DeChambeau, who is playing his first event since turning professional, recorded a one-over 72 to slip five shots off the pace, while England’s Ian Poulter is tied for 69th on seven over after a third round which included three double bogeys.