Three share lead after first round of Farmers Insurance Open

World number three Jon Rahm, meanwhile, struggled to a one-over 73

England’s Aaron Rai shot 8-under 64 at Torrey Pines to tie for the first-round lead with Americans Sam Ryder and Brent Grant at the Farmers Insurance Open (Gregory Bull/AP)

Englishman Aaron Rai shot an eight-under 64 at the Farmers Insurance Open to tie for the first-round lead with Americans Sam Ryder and Brent Grant.

The 27-year-old started at Torrey Pines by birdying the Number 10 on the North Course of the San Diego venue, before collecting seven more birdies on a productive day.