Immelman moved up two to 19th this week after he finished with three straight bogeys on Sunday. Despite the horrid finish, it was enough for Immelman to defeat Justin Rose by a stroke.
Tiger Woods remained in first, followed by Phil Mickelson, Jim Furyk, Steve Stricker and Ernie Els. Adam Scott held the sixth spot for another week.
Rose climbed one spot to seventh, while British Open champion Padraig Harrington dipped one to No. 8. Vijay Singh and K.J. Choi rounded out the top 10.
Rory Sabbatini stayed in 11th, but 2006 U.S. Open winner Geoff Ogilvy and Sergio Garcia switched places from last week. Ogilvy rose to No. 12, while the Spaniard dropped to 13th.
A pair of 2007 major winners, Angel Cabrera and Zach Johnson, took spots 14 and 15, respectively.
Henrik Stenson, Luke Donald, Aaron Baddeley and Immelman earned places 16-19. Niclas Fasth sank one place to 20th and Ian Poulter fell out of the top 20 this week.