Charley Hoffman and Rico Hoey shoot two 63s to get half-way through the American Express event at La Quinta Country Club in California Cheng takes the lead.
Hoffman birdied five of his final seven holes on the Nicklaus Championship Course (one of three holes used in the tournament), while Hoy birdied the fourth hole on the same layout in 10 Caught 8 birdies on the hole.
Hoffman, who had two eagles in the round, has been plagued by back injuries in recent years and is chasing his first PGA Tour victory since 2016.
“Three years ago, I wasn’t very healthy and I wasn’t a very good golfer,” Hoffman said.
“I feel good at the moment. Like I said, I woke up in the morning feeling completely different.
“When I’m healthy and the weather is warm, I feel like I can beat anyone in the world. When it’s cold and my back isn’t feeling good, I don’t think I can beat anyone in the world.”
Hoy added: “For me, this is my second year on tour, so I’m still obsessed with a lot of the guys, Hoffman, Cantlay, Ricky and so on.
“For me, it’s really cool to put my name out there and keep up with them, so that’s all I want to do.”
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The pair topped the leaderboard at 16 under, ahead of Sepp Straka of Austria and Mark Hubbard of the United States on the Pete Dye Stadium course. shot 64) and fellow player Justin Lower were one shot ahead.
Australian Jason Day and American J.J. Spahn are one shot behind, followed by a 13-under group that includes last week’s Sony Open champion Nick Taylor and Nick Taylor. Ricky Fowler shot 62 at Louth Stadium.
Watch the American Express third round live on Sky Sports Golf at 7pm on Saturday. Stream PGA Tour events, major championships and more with NOW