Taiwan sensation Kevin Yu leads Farmers Insurance Open with stellar bogey-free 64

Yu, a former world amateur No 1, carded a bogey-free 64 on the North Course at Torrey Pines, a birdie at the last edging him ahead of America's Patrick Cantlay and Japan's Ryo Hisatsune.

Ireland's Shane Lowry and England's Aaron Rai are among a group a further shot back after opening 66s, along with former Masters champion Hideki Matsuyama, Belgium's Thomas Detry and Alejandro Tosti of Argentina.

Nicolai Hojgaard, who finished seventh at the Dubai Desert Classic, and America's Nick Hardy were the best of those who started on the more difficult South Course – their 67s leaving them amid a large group on five-under-par.

Hojgaard's first start as a full-time member of the PGA Tour came despite jetlag and just nine holes on the North Course in practice.

"You've got to try to find a way," the Danish Ryder Cup star told the PGA Tour website. "I'll just push myself until we feel like the jetlag's gone."

"I think sometimes you can take advantage of not knowing the golf course and you're just thinking about your execution. I felt like that was the only thing I was doing today."

This week's PGA Tour stop at Torrey Pines started on Wednesday to make way for the NFL playoffs on Sunday.

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