|AT&T Byron Nelson|
|-26 Lee (Kor); -25 Spieth (US); -24 Munoz (Col), Matsuyama (Jap); -23 Schauffele (US), Thomas (US), R Palmer (US)|
|Selected others: -22 Schwartzel (SA); -19 Scheffler (US); -18 F Molinari (Ita); -12 Fleetwood (Eng)|
Lee Kyoung-hoon held off Jordan Spieth on the back nine to win the AT&T Byron Nelson for the second year in a row.
The South Korean shot a nine-under 63 at TPC Craig Ranch to win on 26 under, a shot clear of American Spieth.
Spieth began one off the lead held by Sebastian Munoz, who finished in a tie for third on -24, and was aiming for a second title in as many tournaments.
Despite failing to overhaul Lee, Spieth looked in strong form before the US PGA Championship which starts on Thursday.
Spieth travels to Tulsa in Oklahoma in search of a fourth major, one which would see him complete the career Grand Slam by winning all four of golf's biggest titles.
Spieth, cheered on by his home crowd in Texas, shot a five-under 67 and was a shot adrift of Lee for much of the closing stretch.
But Lee holed a pressure putt for par on 17 and made a birdie on the last which proved crucial.
2021 Masters champion Hideki Matsuyama shot a 10-under final round to finish alongside Munoz in third.
American Justin Thomas, the 2017 US PGA winner, finished in a tie for fifth with compatriots Xander Schauffele and Ryan Palmer.