Rory McIlroy lamented his "bad start" after the world number one finished nine strokes behind Charles Schwab Challenge champion Daniel Berger.
McIlroy carded a final-round 74 to end the PGA Tour's comeback tournament tied for 32nd at six under, well adrift of Berger – who prevailed in a play-off against Collin Morikawa on Sunday.
Playing without fans at Colonial Country Club in the Tour's first event since the coronavirus pandemic suspended the season in March, McIlroy had a double bogey and four bogeys from his opening nine holes of the day.
The four-time major champion managed to collect three birdies following the turn, outweighing a bogey at the 15th hole in Texas, but it was too late.
"I got off to a really bad start," McIlroy said. "Hit a loose second shot on the first hole up to the right and then sort of messed around and took bogey there, so not the ideal start.
"The wind was up today. You didn't have to be that much off for it to sort of show and I missed a couple of greens in the wrong spots and made bogeys.
"But you know, played all the way to the end, shot a decent back nine. I was a couple under on the back, but front nine I just got into a rut and played a bad run of holes and obviously that put me out of the tournament."
McIlroy will now turn his attention to the RBC Heritage in South Carolina, where the Northern Irishman will play for the first time since 2009, when he was 19 years old.