Sweden's Carl Pettersson comfortably won the PGA Tour’s RBC Heritage as Luke Donald couldn’t do enough to prevent losing the world No 1 ranking to Rory McIlroy.

Pettersson shot a final round 2-under 69 to finish the tournament with a 14-under total, five shot ahead of Zach Johnson.

"The swing felt good," Pettersson said. "I felt calm. It was a great feeling today."

Donald, on the other hand, needed at least a share of eighth place to keep hold of the world No 1 ranking, despite the fact that McIlroy wasn’t playing this week.

The Englishman began the final round in 52nd place and in need of a stellar performance to hang on to the top spot on the men’s ranking.

His level-par 71 was only good enough to lift him into a tie for 37th with a 2-over total for the tournament, which means McIlroy will move to the top of the Official World Golf Ranking when the new list is released.

It was a relatively easy final round for Pettersson after he birdied three of the first five holes to pull away from the field.

"Getting off to a birdie on No 1 was great," said the Swede, who sank a 24-foot putt at the first and thrived on the outward side throughout the tournament.

"The whole front nine I played really good."

Pettersson said a swing change from three weeks ago in the Houston Open had paid off.

"In Houston I found that new swing key, just opened up my stance and left my left hip clear through the ball," he said. "I've played great. So hopefully this feeling lasts a long time."

"I felt like this year my game was starting to come back to where it was. I played really solid. It's fun to play again, and I kept the weight on."

South African Rory Sabbatini finished in a tie for 17th place after shooting 72 in the final round, while Trevor Immelman and Brendon de Jonge tied for 29th with 1-over totals.

Tim Clark finished on 2-over, and Ernie Els failed to make the cut.

RBC Heritage Official Scores
Player Score
Carl Pettersson -14
Zach Johnson -9
Colt Knost -8
Kevin Stadler -6
Billy Mayfair -6
Matt Bettencourt -5
Boo Weekly -5
Matt Every -4
Charley Hoffman -4
Jim Furyk -4