LOS ANGELES — Dustin Johnson went to No. 1 in the world with a world-class performance at Riviera.
Johnson turned a marathon finish into a Sunday stroll in the Genesis Open. He finished the third round in the morning with a 7-under 64 to build a five-shot lead, stretched it to nine shots at one point in the final round and coasted home to a 71 and a five-shot victory.
Johnson became the 20th player to reach No. 1 since the world ranking began in 1986, ending Jason Day's 47-week stay at the top.
Johnson won for the fourth time against some of golf's strongest fields dating to his U.S. Open victory last summer. All he cared about Sunday was winning at Riviera, one of his favorite courses where he has had chances in four of the last five years.
There was no doubt this time.
Johnson had a one-shot lead when he arrived Sunday at Riviera, which lost 10 hours the previous three days to fog and torrential rain. Johnson had such command of his game that his longest par putt in the third round was from 4 feet, and he closed with three straight birdies to make the final round in the afternoon more of a coronation.
Johnson went 49 straight holes without a bogey, a streak that ended on No. 9 in the final round, and he was sloppy down the stretch when it no longer mattered.
It capped off a strong stretch that elevated Johnson to the top. Not only was it his fourth victory since June, he has finished among the top three in eight of his last 16 tournaments.
Johnson finished at 17-under 267. About the only disappointment was losing a chance to break the oldest 72-hole scoring record on the PGA Tour schedule. Lanny Wadkins won at Riviera in 1985 at 20-under 264.
Thomas Pieters of Belgium and Scott Brown tied in the other tournament. No one had a chance to win as soon as Johnson began the final round with two straight birdies, but Pieters closed with a 63 and Brown shot a 68 to share second place at 12-under 272.