Singh, who set a new single season earnings record on the PGA Tour with the win, now owns a two-point edge over former No. 1 Tiger Woods. Woods will look to regain some ground this week in Ireland at the WGC-American Express Championship, where he is the defending champion.
Ernie Els held onto the third spot, while Masters champion Phil Mickelson stayed put at No. 4. U.S. Open winner Retief Goosen climbed one position to No. 5, knocking Davis Love down to No. 6.
Canada's Mike Weir and Padraig Harrington remained at seven and eight, respectively. Stewart Cink, who won the WGC-NEC Invitational in August, moved up one spot to ninth, while Adam Scott fell to No. 10.
Jim Furyk, Sergio Garcia and Stuart Appleby held their positions from last week. Chris DiMarco climbed one position to No. 14 followed by Chad Campbell, who jumped two spaces to No. 15.
Darren Clarke moved down the rankings to No. 16 this week, while Kenny Perry also dropped down to No. 17. British Open champion Todd Hamilton stayed at No. 18 and Stephen Ames returned to the top 20 at No. 19. Miguel Angel Jimenez followed, staying put at No. 20.
Henrik Stenson won The Heritage on Sunday for his second career victory on the European Tour. The Swede vaulted from No. 215 to No. 132 in the process.