Kevin Na birdied four of the first eight holes and shot a 4-under 66 to cruise to a four-shot victory over Tony Finau at Colonial.
The South Korean-born American opened with a two-shot lead and was in front by at least that many for the final 16 holes.
Na finished 13 under and his third career PGA Tour victory, and second in 10 months, came after putting himself in contention with a second-round 62.
Local favorite Jordan Spieth's strong putting disappeared as the Dallas native finished eight shots back to remain without a victory since his third major title at the 2017 British Open.
It's the first time since 2002-03 that consecutive Colonials were decided by more than one stroke.
Defending champion Justin Rose, who was the highest-ranked player in the field had his third score of par or worse, shooting 70 to finish 5 over.