DeChambeau shot a 6-under 66 to match Uihlein at 16-under 197 at TPC Summerlin. Uihlein, the leader after each of the first two rounds, had a 68.
DeChambeau has four PGA Tour victories, winning three times last season. Uihlein is winless on the PGA Tour.
Lucas Glover was a stroke back after a 61 that he capped with his second eagle of the day. He eagled the par-5 13th on his opening nine and then closed with another eagle on the par-5 ninth. Glover was a stroke off the course record set by J.J. Henry in 2014 and matched by Rod Pampling in 2017. Chip Beck shot a tournament-record 59 in 1991 at Sunrise.
Jordan Spieth remained at 8 under in his season debut, shooting even-par 71.