Johnson wins first outing as world No. 1

Dustin Johnson didn’t flinch when a challenge arrived out of nowhere Sunday, playing mistake-free golf over the final five holes to win the Mexico Championship in his debut as the No. 1 player in the world.

Johnson’s four-shot lead going to the back nine turned into a one-shot deficit when Spanish rookie Jon Rahm ran off an eagle and two birdies at Chapultepec Golf Club in Mexico City. Johnson caught him with a birdie on the par-five 15th, and closed with three pars for a three-under 68 as Rahm three-putted twice to fall back. Rahm would finish tied for third, two behind Johnson and one behind runner-up Tommy Fleetwood.

Johnson won his 14th PGA Tour title and his second in a row. He got to No. 1 two weeks ago by winning the Genesis Open at Riviera in Pacific Palisades. He is the fifth player to win in his first event as No. 1 in the world.

Justin Thomas, who led by one going into the final round in pursuit of his fourth tour victory this season, fell back with a double bogey on the parthree seventh and a bogey on the next hole. He shot a 72 and tied for fifth.

Inbee Park of South Korea closed with an eight-under 64 to win the LPGA’s HSBC Women’s Champions by one stroke at Sentosa Golf Club in Singapore. Despite bogeying the final hole, she finished at 19-under 269 to edge playing partner Ariya Jutanugarn, who shot 66. Third-round leader Michelle Wie struggled to a 72 and tied for fourth with Ha Na Jang and Brooke Henderson at 14 under.

South Africa’s Dean Burmester shot six-under 66 to win the Tshwane Open at Pretoria, South Africa, for his first European Tour title. Finland’s Mikko Korhonen and Spain’s Jorge Campillo finished three shots back.