(Reuters) - Jon Rahm missed a five-foot birdie putt to end the second round one stroke behind leader Andrew Landry at the CareerBuilder Challenge in Palm Springs on Friday.
Spaniard Rahm started the day with the lead, but a five-under-par 67 at the Nicklaus Tournament course at PGA West was not enough to stay in front on another perfect day for low scoring in the California desert.
Landry assumed the mantle with a 65, also at the Nicklaus course, one of three layouts used for the pro-am event.
Landry, a 30-year-old Texan in his second year on tour, posted a 16-under 128 halfway total. Rahm is alone on 15-under, while American Jason Kokrak (67) is next on 14-under.
Birdies are not likely to be as plentiful on Saturday, when the winds are expected to kick up after two calm days.
Five-times major champion Phil Mickelson struggled for much of the round before picking up four birdies in a five-hole stretch for a 68 that still left him 10 strokes from the lead.
Mickelson said his approach shot to his first hole had been an early candidate for "worst shot of the year" but he made amends by pitching in his third shot for an adventurous birdie.
"It was an interesting start," he said, before lamenting the state of his iron play.
"I've been pretty pleased overall with the way I've been driving the ball and displeased with the way my iron game has been.
"I'll go work on it and hopefully improve each round this tournament and build a solid foundation (for upcoming tournaments).
"If I get my iron play back to my normal standard I should have the results I'm expecting. This is the best I've driven it in a lot of years.
"I think it's going to be a good year. It's only the second round of the year. I should get better."