PGA Tour: Zach Johnson shares lead with Alex Noren at The American Express

Johnson hit seven of his 10 birdies on the front nine at La Quinta in California, while Noren had an eagle, nine birdies and a double bogey to finish on 10-under par.

After the day's play, the American Ryder Cup captain said he has "put a lot of good work in as of late".

He said: "Actually been a lot of normal golf work, given what happened last year, with what I was responsible for, which was awesome. Now it's time to get back to work. I've enjoyed the work. I've enjoyed the sweat."

Tied in third place and just one stroke off the lead are Rico Hoey from the Philippines and South African Christiaan Bezuidenhout.

They are ahead of nine players tied at eight-under including Americans Xander Schauffele and Scott Stallings.

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