Brian Stuard assumed the overall lead of the Sony Open in Honolulu after carding a second consecutive five-under round of 65 to dislodge Bae Sang-moon from the top of the leaderboard.
Stuard matched his first-round performance to take the clubhouse lead before Bae teed off and led the field at ten-under with Australian Marc Leishman one shot back after a round of 64.
Michigan-born Stuard's round was highlighted by an eagle on the par-five ninth, with four other birdies helping limit the damage of a bogey on the 17th.
Leishman also eagled the ninth, while carding five birdies with a bogey on the sixth.
He was later joined in a share of second place by Japan's Hideto Tanihara, who collected six birdies and a single bogey to card 65 for the day.
The defence of Bae's lead started poorly as the South Korean bogeyed three holes on his way out before picking up three birdies on his way back in to sign for an even-par 70 and a share of fifth place with Chris Kirk.
The 28-year-old American was unable to match the impressive round of 64 that had left him a shot behind Bae after the first round and he too slipped down the standings following a one-under par 69.
Also sharing fifth place are Jason Kokrak, Jimmy Walker, Chris Stroud and reigning Masters champion Adam Scott, who found five birdies and a bogey to improve on his opening score of 67 by a single stroke.
Kokrak carded a 67 but paid the price for bogeys on the second and third holes as he finished three shots behind Stuard.
Jerry Kelly and Boo Weekley both enjoyed rounds of 67 but sit in a share of 11th place with Hudson Swafford, Greg Chalmers, Matt Every and Justin Leonard.
Meanwhile, last year's runner-up Tim Clark withdrew from the tournament with an elbow injury.