Luke List shot a four-under par 66 to hold a one-stroke lead at the Honda Championship on Saturday while Tiger Woods' 69 ensured he remained within striking distance.
Rory McIlroy slipped back to seven-over overall following a three-over 73, while Shane Lowry is another three back after shooting 75.
List, the co-leader on Friday, birdied the last for a seven-under 203 through three rounds at PGA National in Palm Beach Gardens, Florida.
PGA champion Justin Thomas (65) and Webb Simpson (66) were a stroke behind with Britain's Tommy Fleetwood (67) and American Jamie Lovemark (68) another shot adrift.
Woods, making his third start of the PGA Tour season after a year-long absence following back surgery, birdied his final hole for his first round in the 60s in nearly three years. He was tied for 11th at even par 210 despite two late bogeys.
"Even though I shot 69, it was probably the highest score I could have shot today," the 14 times major champion told CBS Sports.
"I really hit it good. "At least I put myself there where I have a shot going into tomorrow."