Canada's Nick Taylor carded an eight-under 62 to soar to the top of the leaderboard at the half-way mark of the Sony Open in Hawaii, while Ireland's Seamus Power missed the cut.
After getting off to a slow start on the back nine, Taylor's fortunes turned around with a chip-in for eagle on the 18th.
He then picked up five birdies on the front nine to take a two-shot lead into the weekend.
Five players share second place at ten-under, while joint overnight leaders Peter Malnati and Joaquin Niemann, and Collin Morikawa are all a shot further back.
The other leader after Thursday, Jason Kokrak, had a torrid round as he carded three bogeys en route to a 71 to sit tied for 16th.
Seamus Power improved on his first round on 70, hitting four birdies and two bogeys for a 68 that left him on two-under, but that was two shots outside the cut of four-under.