J.B. Holmes surged to the top of the Phoenix Open leaderboard after the second round, while Jordan Spieth's woes continued as the former world number one missed the cut.
American golfer Holmes leapfrogged overnight leader Wyndham Clark with a six-under-par 65 for a one-stroke lead on Friday.
Holmes used an eagle and six birdies, to go with a pair of bogeys, to rise to the top at the halfway stage of the PGA Tour tournament.
A five-time Tour winner, Holmes is 13 under through 36 holes, ahead of countryman Clark (69) at TPC Scottdale in Arizona.
Billy Horschel (68) and South Korea's Byeong Hun An are two shots adrift and tied for third, while Scott Piercy (65) is a stroke further back heading into the third round.
Two-time runner-up Bubba Watson (66), Tony Finau (66) and Jon Rahm (68) are seven under, with Justin Thomas tied for 17th following his second-round 68.
Defending champion Rickie Fowler showed signs of improvement thanks to his six-under-par 65.
After opening with a 74, American star Fowler responded by holing two eagles and three birdies on day two.
However, it was another tough day for three-time major champion Spieth – who missed the cut at one over.
Without a title since the 2017 Open Championship, Spieth's 69 was not enough to rescue the American after his first-round 74.
Spieth, who was tied for 55th at the Farmers Insurance Open, said: "I just really wanted it. I wanted to play the weekend. I had a bunch of buddies coming into town, wanted to kind of give them something to watch the next couple days.
"When I couldn't do the easy part for me, which is putting, that's what was so frustrating. It hasn't been like that. It's been putting saving me, and today it was kind of a little bit of the opposite."