Carl Pettersson has won the RBC Heritage in South Carolina by five shots.
Three birdies at the Harbour Tour Golf Links helped the Swede card a final-round 69 to put him on 14-under-par overall.
His nearest competitor was Zach Johnson as the American's 70 saw him end on eight-under.
Fellow countryman Colt Knost was a shot further back, while Kevin Stadler joined Billy Mayfair on six-under.
Luke Donald relinquished his world number one ranking as he capped a disappointing week by recording a score of two-over. The Englishman had to finish in the top eight of the tournament to keep his number one spot.
Rory McIlroy will be crowned at the top of the new rankings when they are published on Monday.