Harrington matched his career-best ranking thanks to his first major championship win.
The top-five remained the same, but there was plenty of change behind that.
Tiger Woods held steady at No. 1 and was followed by Phil Mickelson, Jim Furyk, Ernie Els and Adam Scott.
Following Harrington at No. 6, was Vijay Singh, who dropped one notch to seventh. Sergio Garcia, a playoff loser to Harrington, jumped five spots to eighth.
With those moves, Henrik Stenson, Geoff Ogilvy and Luke Donald all fell two places to ninth through 11th respectively. K.J. Choi tied for eighth at the British Open. That helped him inch up a spot to 12th.
Steve Stricker was one of three other players who tied for eighth. His amazing turn-around continues, as he moved up three places to 13th this week. Retief Goosen tumbled three to 14th.
Zach Johnson remained 15th, while Rory Sabbatini slipped two to 16th. The next three players -- Angel Cabrera, Paul Casey and Trevor Immelman -- stayed put at 17, 18 and 19.
Stewart Cink jumped up three to close out the top 20. His move bumped Niclas Fasth out of the top 20 to 22nd.