(CNN) -- Former Masters champion Zach Johnson shot a four-under-par 66 on Saturday to seize a one-shot lead going into the final day of the Sony Open in Hawaii.
Johnson: "The guy that makes some putts tomorrow is probably going to come out on top."
Johnson's fourth birdie of a flawless round at the 12th, taking him to 10-under for the tournament, was enough to push him clear of a congested chasing group made up of Shigeki Maruyama, Brian Gay, David Toms and Nathan Green.
"One shot, one errant shot can be a matter of a two- or three-shot swing. So out here, it's just, you know, it didn't really matter," said Johnson, who won at Augusta in 2007, in quotes reported by the UK's Press Association.
"I think that's the beauty of this course. It doesn't surprise me it's congested, and the guy that sticks to his own and makes some putts tomorrow is probably going to come out on top."
Among the chasing four, Toms shot the best score of the day with a five-under 65 to claim his share of second place. Maruyama and Gay both fired 68s, while Australia's Green, who had topped the halfway leaderboard with Tom Pernice Jr., stayed in contention with a 69.
Pernice Jr. appeared to have slipped out of contention for the $972,000 winner's prize with a five-over 75.
The best round of the day came from local favorite Tadd Fujikawa. The 18-year-old started the day with three straight birdies on his way to an eight-under-par 62 that lifted him into a share of sixth place at 202.
"I really made sure I put all my focus and all my effort into every shot that I hit, and I think it paid off," Fujikawa said, in quotes reported by PA. "I'm very happy with today's round."