It's not often you're in full control.
Kuchar was at 14-under 126, matching the lowest 36-hole score of his PGA Tour career.
Cameron Smith's tee shot went 160 yards to the left greenside bunker and his bunker shot went 15 yards to the green where he had a two-putt for bogey on the 204-yard par-3 fourth.
Kuchar shot 22-under 258 for the week in Honolulu and overcame a rocky final-round start to lock up the four-shot win.
Kuchar is 2-2 when he has the 54-hole lead going into the final round.
Kuchar, who had been winless for almost four years until his win at the Mayakoba Classic late in 2018 now appears likely to add a 9th PGA Tour title just three months after his 8th.
He recorded an 18-under 192 total, while Putnam drained a birdie at the last for a 67 to go 16-under. "I didn't find myself in any trouble".
Reavie shot three straight bogeys through holes 11 to 13 but recovered with seven birdies for a round of 66.
Major League Baseball bending rules for Kyler Murray, Oakland Athletics to reach deal
The Oklahoma quarterback has until Monday to declare for the National Football League draft or stick with baseball. Clearly, he wants National Football League first round money to stick with baseball.
American Putnam has sole possession of second place following his first-round 62 at the PGA Tour tournament, while Matt Kuchar (63) is a stroke further back.
Overlooked for last year's U.S. Ryder Cup team after an inconsistent summer, he hit the ground running in the new season and a win at the Mayakoba Classic in November, the eighth of his career, ended a five-year victory drought.
"I feel like my game has turned into a game that can play well at any given course", Kuchar said. Instead, it turned into the American's first top-10 finish since the 2017 WGC-Bridgestone Invitational and his best result since winning the Desert Classic nearly exactly two years ago. There are a lot of good players out there. You don't get many chances like that and it was nice to be there and been able to finish it off. ... Davis Love III shot 6-under 64 to join DeChambeau, as well as Charles Howell III (6 under) and Marc Leishman (2-under 68).
Kuchar was at his best on a number of putts from the 50-foot range.
The Sony Open is more about work than play, and he's having just as much fun.
Putnam picked up two shots on the front nine at Waialae Country Club to hit the front at 18 under.
"Honestly, I didn't think about it at all until after the third one went in", Reavie added.
Jordan Spieth (MC): Spieth bounced back with a 66 following his 73 in Round 1, but it wasn't enough to make the cut (which he missed by one).