Dufner isn't the only player feeling good about his game heading into the Crowne Plaza Invitational at Colonial.
Hunter Mahan is No. 2 behind Dufner in the FedEx Cup standings and the only other two-time winner this season. The past two Colonial champs, Zach Johnson and David Toms, also are playing in the event that opens Thursday.
Johnson has made the cut in all 12 of his tournaments this year, though his last win came two years when he set a tournament-record at 21-under 259 at Colonial. The 45-year-old Toms, coming off a 15th-place tie at Quail Hollow and a 10th-place tie in The Players Championship, got his only victory since 2005 last year at Hogan's Alley.