DeChambeau's bogey-free round Saturday was three shots better than Uihlein's 68. They are both at 16-under through 54 holes at TPC Summerlin.
The round of the day belonged to Lucas Glover, who carded a ridiculous 10-under 61 despite an opening-hole bogey. Glover climbed all the way from outside the top 30 into sole possession of third.
Defending champion Patrick Cantlay sits two shots back of the leaders after posting a 63.
Rookie sensation Cameron Champ is only three strokes off the lead and is looking for back-to-back PGA Tour victories.
Si Woo Kim put together the most up-and-down round of the day, as he opened with five straight birdies before posting a quintuple bogey on No. 6. He then broke his driver on No. 7 and still managed to shoot 69.
Jordan Spieth shot an even-par 71 to slide into a tie for 27th.