Ames, the lone PGA Tour player from Trinidad & Tobago, leaped up 14 spots to No. 17 this week.
Tiger Woods is first for the 256th consecutive week. Ernie Els, Vijay Singh, Phil Mickelson and Davis Love III all held on to their places from the previous week.
Retief Goosen, who won his second U.S. Open title, won his second consecutive start. He captured the European Open and moved up one to six. Mike Weir dropped one to seventh while Padraig Harrington, Jim Furyk and Sergio Garcia rounded out the top-10.
Kenny Perry climbed one spot to 11th and Stuart Appleby jumped two to No. 12. Adam Scott, who won last week's Booz Allen Classic, remained in 13th and Chad Campbell fell three to 14th. Darren Clarke claimed No. 15.
David Toms stayed in 16th, followed by Ames. Fred Couples, Scott Verplank and Jay Haas all dipped one. K.J. Choi, who was 20th last week, slipped one to 21st.