Los Angeles - Dustin Johnson holed out for an eagle to highlight a seven-under par 66 that gave him a two-shot lead Saturday at the PGA Tour Tournament of Champions in Hawaii.
The world number one added six birdies, including a six-footer at the 18th, to give himself a 54-hole total of 16-under 203 on the Plantation Course at Kapalua on Maui.
He was two strokes ahead of fellow American Brian Harman, the overnight co-leader who carded a four-under 69 for 205.
Spain's Jon Rahm was alone in third, matching the best round of the day with a 66 for 207. It was a further stroke back to Americans Rickie Fowler and Jason Dufner on 208.
Johnson, who started the day one stroke behind Harman and Australian Marc Leishman, had three birdies on the front nine before his only bogey of the day at 11.
He responded with an eagle at the par-four 12th, where he holed out from 72 yards out, his second shot landing on the green and rolling in.
"I drove it kind of the left side, I thought I hit a pretty good drive and it was just in the left rough," Johnson said. "I had not very far to the hole. I just landed my shot perfect. It got on the green and it was tracking right towards the hole."
It was part of a solid performance off the tee for Johnson.
"I hit a lot of great iron shots," he said, "but the big key for me is the driver."
Johnson holds the 54-hole lead for the first time since the HSBC Champions in Shanghai in October. There he led by six through three rounds, but stumbled to a closing round 77 to finish tied for second behind Justin Rose.
Johnson said he had moved on from that "fluke day" when he was still getting comfortable with new irons.
Now he's had more time to practice with them, and said he was looking forward to doing battle on Sunday.
"I've got a good game plan around here," he said. "I'm not going to change anything -- just stick to the game plan and try to execute my shots."
Australia's Leishman, who led or shared the lead after each of the first two rounds, couldn't maintain his momentum on Saturday.
He had four bogeys before his only birdie of the day to fall nine off the pace in the elite 34-player tournament for last season's tournament winners.
Leading third-round scores on Saturday in the US PGA Tour Tournament of Champions at Kapalua, Hawaii (USA unless noted, par-73):
203 - Dustin Johnson 69-68-66
205 - Brian Harman 68-68-69
207 - Jon Rahm (ESP) 71-70-66
208 - Rickie Fowler 69-71-68, Jason Dufner 71-68-69
209 - Jhonattan Vegas (VEN) 68-70-71, Pat Perez 72-66-71
210 - Chris Stroud 72-66-72
211 - Daniel Berger 73-70-68, Billy Horschel 70-71-70, Jordan Spieth 75-66-70
212 - Kim Si-Woo (KOR) 69-71-72, Kevin Kisner 70-70-72, Patrick Cantlay 70-70-72, Hideki Matsuyama (JPN) 70-70-72, Marc Leishman (AUS) 67-69-76
213 - Cameron Smith (AUS) 75-70-68, Patton Kizzire 72-72-69
214 - Ryan Armour 71-73-70, Kevin Chappell 74-70-70, Xander Schauffele 72-72-70
215 - Russell Henley 74-69-72
217 - Grayson Murray 74-74-69, Bryson DeChambeau 73-73-71
218 - Austin Cook 74-74-70, Kyle Stanley 70-75-73
219 - Brendan Steele 71-74-74
220 - Hudson Swafford 72-72-76, Wesley Bryan 74-70-76
221 - Justin Thomas 71-75-75
222 - Adam Hadwin (CAN) 73-75-74
223 - Jonas Blixt (SWE) 77-71-75
226 - D.A. Points 76-76-74
230 - Brooks Koepka 78-74-78