Sam Burns had to work a bit harder on Saturday than in the first two rounds but he maintained his lead at the AT&T Byron Nelson as he looks for his second PGA Tour win in as many starts.
After two bogey-free rounds, Burns bogeyed two of the first six holes Saturday at TPC Craig Ranch on the way to a three-under-par 69 for the day.
Despite those struggles, his 20-under through three rounds is the lowest 54-hole score to par in tournament history.
Lee Kyoung-hoon shot 67 to sit one stroke back of Burns for the overall lead.
Three veteran players lurk to challenge that pair in the final round, however, as Dallas native Jordan Spieth, Charl Schwartzel and Matt Kuchar each shot 66 Saturday to sit three back of the lead alongside Alex Noren.
Spieth closed with an eagle at 18 that had the home crowd roaring - just as he had in Thursday's opening round.
This is the fourth time the 24-year-old American Burns has held at least a share of the lead through 54 holes this season.
He did so his last time out, at the Valspar Championship a fortnight ago, and held on for his first PGA Tour win.
If he can match that feat in Dallas, Burns would be the first player since Camilo Villegas in 2008 to earn his first two tour wins in consecutive starts.
South Korean golfer Lee is seeking his first PGA Tour victory. His best showing to date was a tie for second at the Phoenix Open in February, one stroke back of champion Brooks Koepka.
Former world number one Luke Donald (66) is eight back of Burns at 12-under, current world number three Jon Rahm (68) is at 11-under, and 2021 Masters champion Hideki Matsuyama (68) is at 10-under.
Due to storms expected in the area Sunday, the final round will begin at 7am local time from the first and 10th tees.