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.
"It sounds good," Johnson said when asked about being the top player in the world. "I played really great all day. I couldn't have driven it any better. That was a big key."
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.
"He deserves it because he's been playing great golf," Day said.
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.
"No surprise to us players, and I don't think too much surprise to many others," Jordan Spieth said. Spieth ended his streak of 19 consecutive rounds under par on the PGA Tour — and 27 rounds worldwide — with a 72 in the third round.
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 closed with a 63 and Scott Brown shot a 68 to share second place at 12-under 272 .
Fred Couples won the Chubb Classic for his 12th PGA Tour Champions title and first since 2014, rallying to beat Miguel Angel Jimenez at TwinEagles in Naples, Fla. The 57-year-old Couples shot a bogey-free 5-under 67 to finish at 16-under 200 on the Talon Course, three strokes ahead of second-round leader Jimenez.
Jerry Kelly closed with a 66 to tie for third at 11 under in his senior debut. The three-time PGA Tour winner turned 50 in November. Jeff Sluman (68) and Canada's Rod Spittle (69) also were 11 under.
South Korea's Ha Na Jang had an eagle and three birdies over her last six holes for a three-shot victory in the Women's Australian Open. Jang closed with a 4-under 69 to finish at 10 under at Royal Adelaide, three shots ahead of Nanna Madsen of Denmark.
Haru Nomura, the 2016 champion, finished in a four-way tie for third place at 6 under with No. 2-ranked Ariya Jutanugarn of Thailand and Australians Minjee Lee and Sarah Jane Smith.