Luke Donald surrendered his world number one ranking to Rory McIlroy after finishing the RBC Heritage in the United States in joint 37th.
Donald needed a top-eight placing in South Carolina to stay ahead of the Northern Irishman.
However, he could only finish with a second successive level-par round of 71 to end the week on two over.
McIlroy wrote on Twitter: "#1 again without touching a golf club this week.... I wish it was that easy!"
The tournament was won by Sweden's Carl Pettersson, with Donald never in contention after an opening-round 75.
"Is it a concern? No," said Donald, who finished 16 shots behind Pettersson.
"Obviously, I'd have liked to have played a bit more consistently this year. I built it up nicely last year through tournaments and winning a bunch."
Englishman Donald, who lost a play-off to Brandt Snedeker at the same venue last year, made a poor start to Sunday's final round with a double-bogey six on the first, before birdies on the fifth and sixth helped him salvage some respectability.
Pettersson shot a final round of 69 to finish a comfortable winner on 14 under, five shots ahead of American Zach Johnson.
Colt Knost was one shot further back in third after a disappointing 74.
US Open champion McIlroy last month, and will now do so again despite sitting out this tournament.
The 22-year-old is not expected to play again until next month's Wells Fargo Championship in Charlotte, North Carolina.