Rollins, who made the playoff following a blunder by Lancaster on the 72nd hole, birdied the first playoff hole for his maiden title. The 27-year-old became the 13th first-time winner on the PGA Tour this season.
Tiger Woods remained comfortably atop the rankings. The top player in the world was followed by Phil Mickelson, British Open winner Ernie Els and Retief Goosen, who all held their positions from last week.
Sergio Garcia, the fifth ranked player in the world, was in South Korea last week where he captured the Kolon Cup Korean Open for his third worldwide victory of 2002.
David Toms held onto sixth place, while Davis Love III and Padraig Harrington stayed put at seventh and eighth, respectively. Vijay Singh, who finished two shots back at the Canadian Open, remained at No. 9 with Jim Furyk rounding out the top 10.
Nick Price exchanged positions with David Duval to come in at No. 11, while Duval dropped to 12th. Michael Campbell held his position from last week to come in at No. 13 followed by Chris DiMarco.
Leonard, who missed a 40-foot birdie try in his playoff loss to Rollins, moved up four positions to come in at 15th. Rocco Mediate fell one place to 16th followed by Darren Clarke, who held his 17th-place ranking from last week.
Bob Estes came in two spots lower than last week at No. 18, followed by Angel Cabrera, who climbed one rung to 19th. Colin Montgomerie rounded out the top 20 after dropping two places.
Robert Karlsson of Sweden posted a four-shot victory over Trevor Immelman and Paul Lawrie at the European Masters on Sunday. The win was Karlsson's fifth on the European Tour and it was good enough to bump the 33-year-old up 51 places to No. 64 in the latest World Golf Rankings.