Chris Kirk birdied his final two holes to shoot 4-under-par 66 on Saturday to open up a two-stroke lead after 54 holes at the Honda Classic in Palm Beach Gardens, Fla.
Kirk sits at 13-under 197 in search of his fifth win on tour and first since 2015.
Kirk overtook second-round leader Justin Suh, who shot 70 and dropped to third at 10 under. PGA Tour rookie Eric Cole sits alone in second at 11 under after his second consecutive 66 at PGA National Resort & Spa.
England's Ben Taylor (third-round 69) and Ireland's Shane Lowry (65) are within striking distance in a tie for fourth at 9 under, four shots off the lead.
Kirk posted two birdies on the front and four birdies and two bogeys coming in. He was playing with Suh, who had two bogeys and a chip-in eagle for his round.
"I'm just kind of worried about what I'm doing," Kirk said. "Justin is a really nice guy, really great guy to play with, but I'm really not paying a whole lot of attention to what he's doing.
"It was a little bit of a monotonous start I guess for both of us, but you want to go out there and try to make a bunch of birdies and get into the lead, but at the same time, you make a bunch of pars on this golf course, that's good. ... This place is tough."
Cole took advantage of Suh's struggles, recording five birdies -- four on the back nine -- against just one bogey.
"I'm hitting the ball well, which is always good. It's important around here," Cole said. "There's so many tough shots. But I felt good today, which was really nice. I felt relatively comfortable out there and hit some good shots when I needed to."
Suh's lone bright spot came at the par-4 12th hole, where he holed out from 153 yards on his second shot.
"I hit an 8-iron. Just cut off an 8-iron. It was in off the left and it came out great," Suh said. "I was asking for it to sit. My caddie wanted it to go, and it was right in the middle, so it was perfect."
Ryan Brehm posted a 64, good for low round of the day. He vaulted 45 spots up the leaderboard to put himself at 5 under, tied for 15th.
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