Weir, who will be one of the No. 1 seeds in this week's WGC-Accenture Match Play Championship, jumped up two spots from sixth last week as he held off a late charge at Riviera by Shigeki Maruyama.
Tiger Woods, the defending Match Play champion, remained in first for the 237th consecutive week and for the 308th week overall. He is 23 weeks short of Greg Norman's all-time record of 331 weeks.
Vijay Singh held on to second place, followed by Ernie Els, who will not play in the Accenture Match Play Championship because his daughter starts school on Monday.
Weir came in fourth followed by Davis Love III and U.S. Open champion Jim Furyk, who each fell one spot. Love will be a one seed starting on Wednesday while Furyk is out of the event with a wrist injury.
Retief Goosen, Phil Mickelson and Kenny Perry kept their places from last week while Stuart Appleby, who finished third at the Nissan Open, climbed three to 10th.
David Toms, the runner-up to Woods last year in the Match Play, Padraig Harrington and Darren Clarke each dipped one to accommodate Appleby's move up the rankings.
Jonathan Kaye stayed in 14th and Chad Campbell leaped two to 15th. Robert Allenby remained 16th but Nick Price dropped two to No. 17. Fredrik Jacobson and Thomas Bjorn switched places from last week with Jacobson taking 18th and Bjorn coming in 19th. Fifty-year-old Jay Haas rounded out the top-20 again this week.
Maruyama vaulted up 13 spots to No. 22 this week but the big move came from John Daly. Daly, who won the Buick Invitational a week ago, came in fourth at Riviera and moved up 21 rungs to No. 64 this week. In the last two weeks, Daly has rocketed up an amazing 235 places.
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