Tour rookie Keegan Bradley, who has won two events in 2011, shot a six-under 64 to seize a two-shot lead after the first round of the PGA Tour Championship. World No. 1 Luke Donald fired a four-under 66 and was joined by Jason Dufner in a tie for second, two strokes behind Bradley who won the 2011 PGA Championship at the nearby Atlanta Athletic Club course. Donald finished up with a par on 18 after a weather delay on the East Lake Golf Club course. Rain began to fall after the final groups made the turn and officials sounded the horn with two groups left, resulting in an almost half hour rain delay. Aussies Adam Scott and Jason Day were part of a group of five in a tie for fifth place at three under. The players are not only battling to win this tournament, but also the PGA Tour playoffs. The 26-year-old Bradley is a long shot to win the FedEx Cup playoffs but still has a chance at making the USA Presidents Cup team with a strong showing here. "The cliche is to say that I'm not thinking about it, but literally probably every third hole -- or maybe even less -- it pops into my mind," Bradley said. "I really want to be on the team, but I want to earn my way onto the team, just like I'm going to have to. If the captain and assistant captains think I've done enough to get on the team, they're going to pick me." His opening round Thursday included four birdies on the back nine. Dufner and Bradley are no strangers in big tournaments. Dufner had a four-shot lead at the PGA Championship with three holes to play until he made three straight bogeys and wound up losing in a three-hole playoff to Bradley. "Maybe he's having some of the same feelings - very comfortable on this type of golf course... with the conditions maybe a little more severe at Atlanta Athletic Club off the tee," Dufner said. "But he's having a good day. Hopefully, we'll be paired tomorrow. That will be a little interesting, I guess. Maybe some thoughts here or there will come back and forth."